Development economists study both anthropometry and intra-household allocation. In these literatures, the Demographic and Household Surveys (DHS) are essential. The DHS censors its anthropometric sample by age: only children under five are measured. We document several econometric consequences, especially for estimating birth-order effects. Child birth order and mothers’ fertility are highly correlated in the age-censored anthropometric subsample. Moreover, family structures and age patterns that permit within-family comparisons of siblings’ anthropometry are unrepresentative. So strategies that could separate birth order and fertility in other data cannot here. We show that stratification by mother’s fertility is important. We illustrate this by comparing India and sub-Saharan Africa (SSA). Children in India born to higher-fertility mothers are shorter, on average, than children of lower-fertility mothers. Yet, later-born children in India are taller, adjusted for age, than earlier-born children of the same sibsize. In SSA, neither of these associations is large. •The DHS censors its anthropometric sample by age: only children •We document econometric consequences, especially for studying birth-order effects.•Strategies that could separate birth order and fertility in other data cannot here.•We show that stratification by mother’s fertility is important.•We illustrate this by comparing India and sub-Saharan Africa. Although the DHS asks about outcomes . A thirdoutcomes .Thus, the fact that the DHS censors the height sample by age matters for researchers using within-family empirical strategies, and especially for those studying birth order. In particular, ’s recommIn Section Section e.g.American Economic Review of height and birth order in the DHS.We use stratification in non-parametric summaries in Section 2We compare India and SSA, two populous regions at different points in the fertility transition. For India, we use the 2005–6 Indian DHS, which is called the National Family Health Survey-3 by the Government of India. For SSA, we use 27 comparably-timed DHS survey rounds from 25 countries. To study birth order, we exclude multiple births such as twins.We use three samples from the Indian and SSA DHS birth histories:•Full birth history:•Main height sample:•Mother-fixed-effects subsample:last-born and next-to-last-born children can be compared. But comparing first-borns with third-borns in sibships of 3, for example, is constrained by the age censoring. Panel (c) focuses on children’s eligibility for the mother-fixed-effects subsample. Consider using these data to answer the seemingly simple question of whether third-born children tend to be shorter than their first-born siblings. In the framework of Panel (c), a first-born child is 2 or more from last-born, if in a sibsize of 3 or more. Another implication of The few large families in which early-borns are young enough to be measured are negatively selected for their families’ short birth spacing. For example, controlling for child age and sex, third-borns in India in sibships of 3 with a measured first-born sibling are shorter than third-borns without a measured first-born sibling by a gap almost as large as that between urban and rural Indian children.Additionally, these measured pairs are at the two extreme ends of the five years of measured age. The average first-born and third-born in the height subsample are both 28 months old  but are 51 and 8 months old, respectively, among the selected subset that can be compared with one another within households. Age predicts height-for-age. These facts illustrate that the age-censored height sample is not constructed to permit such within-sibship comparisons.3Birth order is necessarily correlated with other variables that are correlated with child outcomes, including child age, mothers’ fertility, mothers’ age at birth, and birth spacing. These identification challenges have been well-studied. As  mothers . In an eAverage fertility is lower in India  than in 4Suppose for example that larger families were poorer and had children in worse health, but within each family all children were exactly equally healthy. A regression including children from multiple families of health on only birth order would find a negative association between being later-born and health . But this finding would be a spurious artifact of the bias created by the key omitted variable of sibsize.Holding sibsize constant may be both especially important and especially challenging when a sample is age-censored to young children, as is the DHS anthropometric subsample. Techniques in the literature that are thought to account for a group-level omitted variable can fail when selection into the group  is endogenous compare .a priori that there is zero causal effect of birth order on these dependent variables, because the “outcomes” must be the same for all siblings. As standalone research, these regressions make no sense. But they illustrate the challenges of using the height subsample. If a regression with such a specification does not yield a zero coefficient, we should investigate whether there exists a threat to identification.In negative coefficients for mother’s height in India but positive coefficients in SSA, matching the slopes in panel (b) of In the first two columns of each panel, sibsize is not controlled at all. Compare these results with the fertility gradients in once sibsize is conditioned upon, the presence of earlier-birth-order observations is a marker of disadvantage. This yields the spurious positive coefficients on later birth order in columns 4 and 9. Columns 3 and 8 do not show these positive coefficients because their sample is not age-censored.In the next two columns of each panel, indicators for sibsize are included as regression covariates. Columns 3 and 8 use the full birth history; columns 4 and 9 use the height subsample. If the full birth history is used, the estimate comes close to the correct zero coefficient. But in the height subsample, the coefficients are positive and large, and smaller in India than in SSA (more negative in India in a difference-in-differences sense). This is because of selection into the height subsample. If a mother has any living children young enough to be in the height subsample, then the last-born child  is always included. Conditional on sibsize, earlier-born children are included only in cases of short birth spacing. Shorter birth spacing predicts worse outcomes for children. So Finally, columns 5 and 10 further restrict the height subsample to stratify down to sibsize of 2. Here, the regression coefficients are correctly zero. Might mother fixed effects – which would compare (some) children with their own siblings – work instead? In the regressions in 5How can researchers investigate the relationship between birth order and height, given these challenges? The simplest place to start is to plot stratified, non-parametric summary statistics. HO norms . For claPanel (a) plots local polynomial regressions of HAZ on age. No further controls, residualization, or restrictions are used beyond stratifying the sample by birth order and sibsize. There is a well-studied relationship between HAZ and age in children under two in developing countries : mean HAIn SSA, neither birth order nor sibsize is predictive of HAZ: within a sibsize, at the same age, HAZ lines for different birth orders overlap. India is different. Across sibsizes, there is a downward trend: children from larger sibsizes are shorter, on average. Within a sibsize, at the same age (and where the same age is measured for both birth orders), later-born children are taller, on average. More specifically, in sibsizes of 2 there is no evidence that first-borns are taller than second-borns. The rest of this paper considers how to compress the information in Panel (a) of Another important lesson of Panel (a) in In the birth-order literature, there is a standard non-parametric tool described in detail by with more siblings are shorter than children with fewer siblings at the same age.As in Panel (a), three patterns are clear in Panels (b) and (c): (1) that in India higher sibsize is associated with shorter child height; (2) that there is no later-born height disadvantage in India; and (3) that neither of these patterns is pronounced in SSA. In other words, in India, children 6What would we learn if we attempted to summarize We apply the methodological observations of this paper to ask whether the correlations between birth order and sibsize in India and SSA can be understood as causal effects. More specifically, we ask what JP would have found if they had stratified by sibsize.Our purpose here is to illustrate the importance of endogenous fertility in the age-censored DHS child height subsample — not to assess each econometric choice of JP. JP recognize the potential that sibsize could be an important confounder. They discuss the threat and implement several robustness checks. Here we show how these strategies are limited by the structure of the available data.6.1JP estimate the following regression specification, their Eq. different between India and SSA, where larger families are advantaged by some relevant measures). They argue against including a regression control for sibsize, as observed at the time of the survey, because women’s childbearing careers will often be incomplete: “the nature of DHS sampling implies that a large fraction of households in our sample have not completed childbearingJP are aware that sibsize could be an omitted variable in their analysis. They write: “Higher birth order children are more likely to come from larger families, and family size could be correlated with child height; family size could affect child height via its effect on the available resources per child, plus larger families tend to be poorer” (p. 2609; they do not, however, raise the possibility that this correlation may be In many other birth-order studies, age is held constant in the dependent variable, so the time period of interest differs across siblings: for example, Eq. 6.2Throughout, we have used the same set of Indian and SSA survey rounds as JP.Column 1 of Panel A is our replication of JP’s main result, presented in their column 2 of their Table 2. Our estimates in Column 1 are quantitatively similar to what JP find: First-born children in India with height measured in the DHS are taller, on average, than first-born children of the same age in SSA; HAZ differences by birth order in SSA are small; and the average later-born child with height measured in the DHS in India is shorter than the average first-born with height measured. In Section The next step is to stratify by sibsize. To permit a clear comparison with our stratified results, column 3 restricts the sample to the minority subsample with two measured height observations per family. In the four combinations of columns 1 and 3 of Panels A and B, the interactions of interest between birth order and an India indicator are quantitatively stable. The non-interacted coefficient on India becomes much smaller because this coefficient reflects first-borns, many of whom are now excluded. Restricting the sample to sibling pairs excludes all first-borns in sibsizes of 1: these first-borns with no siblings can teach us little about within-household discrimination by birth order, but they pose a threat to identification because, as Columns 4 through 7 account for sibsize by holding it constant in stratified samples: columns 4 and 5 restrict the sample to children in sibsizes of 2; columns 6 and 7 restrict the sample to children in sibsizes of 3. 91% of Indian families in the sample in which a first-born and a second-born both have measured height are from a sibsize of 2. Columns 5 and 7 further include mother fixed effects. Stratifying by sibsize eliminates or reverses the negative interaction between India and later birth order, with or without mother fixed effects.6Finally, for completeness and despite concerns raised in Section In short, sibsize makes an important difference. 76.3Because of the correlation between child height and sibsize, the negative correlation between birth order and child height in India cannot be interpreted as a negative effect of birth order. Some results even suggest a positive effect. Our conclusion, however, is that the structure of the available DHS data prevents researchers from being able to interpret these results with confidence as an effect of birth order on child height.within-family process of discrimination. They write in their abstract: “We posit that India’s steep birth order gradient is due to favoritism towards eldest sons, which affects parents’ fertility decisions and resource allocation across children”. But, as Beyond its econometric importance for internal validity, the age-censoring of the DHS height subsample also influences the external validity of these results. JP propose that their results are due to a One question is why JP’s analysis – despite its extended set of robustness checks – suggests a negative relationship between height and birth order, particularly in a robustness check with mother fixed effects. It is understandable that an econometrician might consider mother fixed effects as a solution for confounding heterogeneity at the sibship level. The fact that sibsize can be an omitted variable in a study of birth order is simple and straightforward. The failure of mother fixed effects, in an age-censored subsample, for two estimates of the effect of birth order in two populations, on an outcome measured at different ages for different siblings, is not. We propose that the age-censoring of DHS data causes an instance of what omitted variable here to be controlled, but rather is an interactor with birth order that marks heterogeneity in the parameter of interest. Because birth spacing is a difference between two siblings and is a correlate of age, it violates the strict exogeneity requirement of fixed effects (8In this case, using mother fixed effects selects for very short birth spacing . Short b effects .8A separate example of the consequences of mother fixed effects concerns SSA. JP’s summary statistics and main Eq. advantage in India when studying consequences for early-life mortality in the full birth histories of the same set of DHS surveys that we and JP use. They find similar results whether they stratify by sibsize, use mother fixed effects, or include regression controls for sibsize directly. DHS mortality data are not censored by child age. Nor are age controls involved, because infant and neonatal mortality rates are age-specific. Finally, DHS birth histories include children of mothers whose fertility is long-completed. Coffey and Spears present evidence that such a later-born neonatal survival advantage in India reflects improvements in maternal nutrition over the course of childbearing careers, in a population where young women are especially likely to be underweight. These facts are consistent with the interpretations we have presented here — and with our argument that stratification by sibsize can be an important tool in some contexts.Of course, mother fixed effects can be a useful tool in data without the constraints of the DHS anthropometric subsample. Dean Spears: Participated in all aspects of this research. Diane Coffey: Participated in all aspects of this research. Jere R. Behrman: Conceptualization, Writing – review & editing.


The aim of this study was to analyze the glymphatic system function and its relationship with clinical characteristics, global diffusion tensor imaging (DTI) parameters, and global structural connectivity in treatment‐naïve patients with newly diagnosed focal epilepsy.This retrospective single‐center study investigated patients with focal epilepsy and healthy controls. All participants underwent routine brain magnetic resonance imaging and DTI. DTI analysis along the perivascular space (DTI‐ALPS) was used to evaluate glymphatic system function. We also calculated the measures of global DTI parameters, including whole‐brain fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD), and performed a graph theoretical network analysis to measure global structural connectivity.p = 0.861) between the groups. However, statistically significant associations were found between the DTI‐ALPS index and age , FA , MD , AD , RD , and the assortative coefficient  in patients with focal epilepsy.A total of 109 patients with focal epilepsy and 88 healthy controls were analyzed. There were no significant differences in the DTI‐ALPS index (1.67 vs. 1.68, The main finding of this study is that DTI‐ALPS index is significantly correlated with global DTI parameters and structural connectivity measures of the brain in patients with focal epilepsy. In addition, DTI‐ALPS index decreases with age in these patients. We conclude that the DTI‐ALPS index can be used to investigate glymphatic system function in patients with focal epilepsy. DTI‐ALPS index is correlated with the global DTI parameters and structural connectivity of the brain in focal epilepsy.DTI‐ALPS index decreases with age in focal epilepsy patients.The DTI‐ALPS index can be used to investigate glymphatic system function in patients with focal epilepsy. Furthermore, we sought to use correlation analysis to understand the relationship between DTI‐ALPS index and clinical characteristics, global DTI parameters, and global structural connectivity. We hypothesized that there would be significant associations between these factors in patients with focal epilepsy. These confirmations will contribute towards discovering the pathogenesis of epilepsy.22.1This was a retrospective study conducted at a single epilepsy center.We included patients with epilepsy based on the following eligibility criteria:  from the hospital's electronic medical records.As a control group, we included age‐ and sex‐matched healthy controls from one of our previous studies .All MRI scans of the patients with focal epilepsy and healthy controls had been obtained using the same 3T MRI scanner with a 32‐channel head coil . In our epilepsy patients, these had been obtained as part of their routine work‐up. DTI was conducted using spin‐echo single‐shot echo‐planar pulse sequences with a total of 32 different diffusion directions . We read the DTI raw files in the Digital Imaging and Communications in Medicine standard format. Then, we did correct the eddy current and phase distortion artifact. We set up a mask to filter out the background region, increase reconstruction efficacy, and facilitate further visualization. We performed reconstruction applying the DTI method to characterize the major direction of water diffusion and subsequently fiber tracking using default parameters. Whole‐brain seeding was conducted with a total of 10,000 seeds, and the angular threshold was 60 °. Tracks of less than 30 mm length were discarded. The automated anatomical labeling template was used for brain parcellation, and every white matter fiber was evaluated for extreme points.We processed the DTI data using the DSI Studio software, version 2021 May  threshold by 0.001 of the sum to obtain the network measures. Graph theoretical analysis views brain connections as a graph and applied graph‐based measures to analyze it. A graph is defined as a set of nodes or vertices and the edges or lines between them. We used built‐in atlas provided in DSI studio, and we conducted a spatial normalization with the linear transformation. Finally, we performed a graph theoretical network analysis and calculated the measures of global structural connectivity from the connectivity matrix at fixed density, including the assortative coefficient, mean clustering coefficient, characteristic path length, diameter, radius, global efficiency, local efficiency, small‐worldness index, and transitivity. We used the weighted network measures in which the connectivity matrix is normalized so that the maximum value of the matrix is one.2.5We drew a rectangular ROI and obtained the fiber orientation and diffusivities in all three directions along the x‐, y‐, and z‐axes as voxel levels. Among the several voxels, we selected one voxel for each fiber on the same x‐axis , which showed the most frequent orientation in each fiber. The DTI‐ALPS index was calculated using the following formula: between the groups.We performed the Bonferroni correction for the multiple comparisons of the measures of global DTI parameters and global structural connectivity .All statistical analyses were performed using MedCalc® Statistical Software, version 20 .One hundred and nine patients with focal epilepsy and 88 healthy controls were enrolled in the study. Table 4.2p = 0.003), whereas the FA, MD, and RD did not differ statistically significantly after the Bonferroni correction between them.Table 4.3There were no statistically significant differences in the measures of global structural connectivity  between the groups Table .4.4p = 0.86)  Figure .4.5p = 0.01), age at seizure onset , FA , MD , AD , RD , and the assortative coefficient  in patients with focal epilepsy  and seizure frequency , and the measure of structural connectivity, including mean clustering coefficient , characteristic path length , diameter , radius , global efficiency , local efficiency , small‐worldness index , and transitivity , were not significantly correlated with the DTI‐ALPS index.However, other measures of clinical characteristics, including duration of seizures , FA , MD , AD , RD , and the assortative coefficient  in healthy controls.Significant correlations were also observed between the DTI‐ALPS index and age , characteristic path length , diameter , radius , global efficiency , local efficiency , small‐worldness index , and transitivity , were not significantly correlated with the DTI‐ALPS index.However, other measures of structural connectivity, including mean clustering coefficient  the DTI‐ALPS index was not statistically significantly different between these patients and healthy controls, suggesting that there was no difference in glymphatic system function; 2) negative correlations existed between the DTI‐ALPS index and subjects’ age, indicating that their glymphatic system function decreased with aging, and 3) statistically significant correlations existed between the DTI‐ALPS index and the FA, MD, AD, RD, and assortative coefficient, demonstrating that the glymphatic system function was correlated with global DTI parameters and structural connectivity. These findings confirmed our hypothesis.The strengths of our study were: 1) It was the first to evaluate the DTI‐ALPS index in patients with focal epilepsy; 2) We only analyzed patients with newly diagnosed focal epilepsy and a normal brain MRI, increasing the homogeneity of patients and excluding potential effects of ASM on DTI‐ALPS index; and 3) We enrolled large patients with focal epilepsy, which was possible because of the specific routine epilepsy MRI protocols at our center that include DTI.Regarding our finding that DTI‐ALPS index decreased with age in both patients with focal epilepsy and healthy subjects, a previous study found that age was related to a steep decline in glymphatic system function in the brain of wild‐type mice (Kress et al., We found that whole‐brain FA was positively and MD was negatively correlated with the DTI‐ALPS index, which corresponds to previous results. FA reflects the main direction of water diffusion within a given voxel and MD is the rate of water diffusion, irrespective of its direction (Assaf & Pasternak, Our study showed a positive correlation between the DTI‐ALPS index and assortative coefficient as one of the measures reflecting global structural connectivity. Increasing evidence exists that focal epilepsy is a network disease, and DTI is used to assess structural brain connectivity (D. A. Lee et al., However, we could not find any differences in the DTI‐ALPS index between patients with focal epilepsy and healthy controls, suggesting no alterations in glymphatic system function in focal epilepsy. This finding was inconsistent with previous reports showing glymphatic system dysfunction in patients with epilepsy (Liu et al., Only a few studies have used DTI‐ALPS to assess the glymphatic system function in neurological diseases, i.e., Alzheimer's disease (Taoka et al., There are several limitations to this study. First, this study was retrospectively conducted at a single epilepsy center. Multicenter studies with larger sample sizes are required to confirm our findings. Second, this was a retrospective study. Follow‐up data to investigate the DTI‐ALPS index in patients with focal epilepsy are needed to determine the causal relationship among DTI‐ALPS index, global DTI parameters, and structural connectivity. Third, although we only analyzed patients with focal epilepsy and normal brain MRI, the origins of epileptic seizures varied.6The main findings of this study are that DTI‐ALPS index is significantly correlated with global DTI parameters and structural connectivity and decreases with age in patients with focal epilepsy. However, the DTI‐ALPS index in newly diagnosed focal epilepsy patients with normal brain MRI does not differ from that in healthy controls. The DTI‐ALPS index can be used to investigate glymphatic system function in patients with focal epilepsy.All authors have no conflicts of interest to declare at the time of submission.DA Lee, BS Park, and KM Park were associated with conception and design. BS Park, J Ko, S Park, JH Park, IH Kim, YJ Lee, and KM Park were associated with the acquisition of data, analysis, and interpretation of data. DA Lee, BS Park, and KM Park drafted and revised the manuscript. KM Park provided the final approval.None.https://publons.com/publon/10.1002/brb3.2504The peer review history for this article is available at


This scoping review aims to identify the evidence and the factors influencing the outcomes of early discharge of both healthy first-time mothers and newborns.Systematic searches were conducted using four databases up to February 2021, and a search for grey literature was performed. A total of 2030 articles were identified and reduced to 13 articles, and one article was added through chain search in reference lists. The aims of the identified studies, the methodology, participants, inclusion and exclusion criteria, and the setting, context, and findings are summarized.A total of 14 studies were included. A thematic analysis identified the following factors influencing the outcomes of discharge within 24 hours after birth: parental education in pregnancy, perinatal information before discharge, sources of support, and follow-up strategies after discharge. Also, the analysis identified outcomes such as breastfeeding, parents' experience and readmission of the newborn that may be influenced when first-time parents are discharged within 24 hours after birth. Findings in this review highlight the importance of identifying factors and outcomes related to early discharge. However, because of the heterogeneity in methodology, terminology and assessment procedures used in the retrieved articles, the generalization of study results is limited.A gap in the literature about the outcomes of discharge within 24 hours after birth has been identified. Future studies with strong evidence are needed, defining criteria, context, and intervention. Furthermore, in Western countries, the length of stay after birth in a facility care unit has steadily decreased since the 1950s3. In addition, a study from Denmark from 2017, including 1202 first-time mothers, found that 9.1% of first-time mothers were discharged within 12 hours after birth4. Since 2018, healthy first-time mothers with uncomplicated births have been discharged within four hours after birth, as standard procedure at three larger maternity wards in Denmark. Therefore, the new tendency in Denmark leads to the interest of what evidence exists about the early discharge of first-time mothers. International recommendations on early discharge strategies for both healthy first-time mothers and newborns differ regarding the time of discharge after birth, the criteria for early discharge, and the follow-up strategies. The purpose of the recommendations is to prevent maternal and neonatal morbidity and mortality and prevent readmission9. For this reason, the United States government introduced the ‘Newborns’ and Mothers’ Health Protection Act’ in 1996, based on the recommendations of the American Academy of Pediatrics and the American College of Obstetricians and Gynecologists11. The law ensures coverage of a hospital stay for 48 hours following vaginal birth for parents with a group health plan or individual health insurance policy10. However, the World Health Organization (WHO) recommends staying in a healthcare facility for at least 24 hours after an uncomplicated birth7. The Spanish Association of Pediatrics recommends discharge from the hospital after 48 hours after birth for healthy newborns5. Furthermore, national guidelines from the United Kingdom, Denmark and Norway recommend that the time for discharge is based on discussion and agreement between the healthcare providers and the parents9. The overall criteria for discharge 24 hours after birth, recommended by WHO, are that the mother’s bleeding is controlled, the mother and newborn must have no signs of infection, and the baby should be breastfeeding well7. All the guidelines describe physical and psychosocial risk factors for the mother and newborn that must be considered by the healthcare professionals before early discharge after birth9, for example, signs of pre-eclampsia, postpartum hemorrhage, domestic abuse, and signs of neonatal jaundice9. Furthermore, the recommendations for follow-up strategies after discharge within 24 hours after birth differ. The recommendations include a home visit within 24 hours after birth, a pediatric check-up three to four days after birth, or a home visit by a midwife on the second or third day after birth9.Discharge within 24 hours after birth is not unusual for both healthy first-time mothers and newborns. A study on the length of stay after birth, including 30 low-income and middle-income countries, found that 28% of first-time mothers were discharged within 24 hours after a vaginal birth20. The outcomes of early discharge examined in the reviews included postpartum hemorrhage, infection, breastfeeding, postpartum depression, neonatal dehydration or malnutrition, the father’s anxiety about caring for the newborn after discharge, and the parents' satisfaction with early discharge20. However, the definition of early discharge in the reviews varies from 6 to 96 hours after birth20. Early discharge for first-time parents is a broad subject, and a scoping review provides the opportunity to explore the extent and nature of the existing literature21. Our preliminary literature search showed that most studies define early discharge as discharge within 24 hours. However, early discharge was in some studies defined as within 8 hours, 17 hours, or the day of birth. To ensure that we identified all studies that addressed early discharge, we chose 24 hours as the inclusion criterion. The purpose of this scoping review is to aid maternity wards in developing an early discharge policy. Therefore, this scoping review aims to identify the evidence of: 1) factors that influence firsttime parents' decision or readiness to be discharged within 24 hours, and 2) outcomes for healthy first-time parents and healthy newborns who were discharged within 24 hours after birth and which factors influence these outcomes.Reviews on early discharge after birth report factors that can influence the outcomes of early discharge of both healthy mothers and newborns. The influencing factors found in the reviews include the criteria for early discharge, parental education in pregnancy, information before discharge, infant feeding, follow-up strategies, and availability of support from family and health professionals after discharge21. This was the case for the outcomes and the factors influencing the outcomes of early discharge of healthy first-time parents. The PRISMA-ScR; Checklist and Explanation was used as a guide in structuring this article22. Furthermore, the Levac et al.21 methodological framework, with a six-step approach for conducting a scoping review, was used to guide the systematic literature search of this scoping review.A scoping review provides the opportunity for summarizing the existing research in a field where the literature is heterogeneous in terms of the study design, theoretical framework, and outcome measurementThe research questions included: ‘What evidence exists about factors that influence first-time parents' decision or readiness to be discharged within 24 hours?’ and ‘What evidence exists about outcomes and factors that influence the outcomes of discharge within 24 hours after birth for healthy first-time parents and healthy newborns?’.The authors conducted a comprehensive systematic literature search to identify relevant articles. The inclusion criteria were first-time parents and healthy mothers with an uncomplicated vaginal birth, healthy infants defined by the primary studies’ authors, and infants born at a gestation age between 37 to 42 weeks. We included first-time parents discharged within 24 hours after birth or described as discharged within one day after birth, compared to discharge later than 24 hours after birth. If a study included both first-time and multiparous parents, a clear distinction between the results for first-time and multiparous parents was required for inclusion. Also, a clear distinction between the results for discharge before or after 24 hours after birth, and a distinction between the results for vaginal birth and caesarean section were required for inclusion. Quantitative, qualitative, and mixed methods types of studies were also included. Study designs as metaanalysis, reviews, experimental and observational study were included. Conference abstracts, dissertations, books, essays, editorials, commentaries, and audio accounts were excluded. Articles written in English, Danish, Norwegian, and Swedish were included.Pubmed, Cinahl (with full text), EMBASE (Ovid), and Scopus were systematically searched from the inception date of each database to 8 October 2019. Keywords in the search included: first-time parents , first child  and length of stay after birth . The search included synonyms and variations of the keywords combined with Boolean operators. A combination of search techniques was used, including controlled vocabulary thesaurus terms  and a free-text search of all the synonyms and variations of the keywords were used. Furthermore, to identify any grey literature, a search in Google Scholar was performed. Finally, the searches were supplemented with forward and backward chain search in citations and reference lists from the identified literature and relevant guidelines. The search strategies from all databases are shown in the Supplementary file.® according to the inclusion criteria23. Disagreements were discussed and resolved by consensus of the authors. An updated search was performed on 22 February 2021, based on the search strategy described above.The authors independently screened the records in CovidenceThe data were charted in stage four, according to Levac et al., and a descriptive numeric summary and a thematic analysis guided by the research question was provided. Each study was narratively described. Authors VL and DM collaborated thoroughly in extracting the data from the identified studies.Based on the search strategy, 3750 citations were identified. After removing duplicates, 2030 studies were screened independently, by authors VL and PSG, based on title and abstract, and 1892 studies were irrelevant. Authors VL and DM screened independently a total of 138 studies based on full text. A total of 126 studies were excluded. The updated search identified a total of 366 studies, and one new study was included. Thus, a total of 13 studies were included, and one article was added through chain search in reference lists, as shown in the PRISMA flow diagram .As illustrated in 33. However, some of the studies use other definitions like discharge on the day of birth34, discharge within one day or less35, discharge six to eight hours after birth36, or six to 17 hours after birth37.Most of the included studies define early discharge as taking place within 24 hours after birth37. Other studies used criteria for early discharge that included all routinely discharged healthy newborns at term34 or all mothers discharged with a live newborn35. One study25 had the following specific criteria for early discharge:The definition of an uncomplicated birth is not specified in most of the studies. In six studies, the criterion for early discharge is described as an uncomplicated pregnancy and birth, without further definitionGravida 1Abortion 0No history of infertilityAge of the mother >20 yearsVaginal birthTemperatures below 38.0℃No postpartum hemorrhageBlood pressure below 140/90 mmHg38–41 weeks gestation2500–4500 g weight at birthThe newborn has a stable temperature and can feed, i.e. suck and swallow.The factors that might influence the first-time parents' decision or readiness to be discharged within 24 hours after birth identified in this scoping review were parental education, social support, and follow-up strategies after discharge. The following four outcomes of early discharge were identified: the parents' sense of security, the parents' satisfaction with early discharge, breastfeeding, and neonatal readmission. In addition, five factors that might influence one or more of the outcomes were parental education in pregnancy, social support from relatives, follow-up strategies, availability of support from healthcare professionals, and the parents' readiness for discharge.37. One group of parents had ‘decided beforehand’, and another group wanted to ‘take it as it comes’37.A study found that first-time parents can be divided into two categories related to the parents' choice of early discharge after birth24. Of the 10 hours of classes, four and a half hours were focused on postnatal issues, but further details were not described24. Of the 59 mothers in the study, eight mothers changed their opinion from a preferred longer stay to being discharged 24 hours after birth. Only three of the mothers attributed their change in opinion to the information given in the prenatal class24. A total of 20 of the 59 mothers changed their opinion after birth, from wanting discharge within 24 hours after birth to wanting discharge later. However, 15 of these mothers attributed the change in opinion to the birth experience and not the prenatal education24. Lemmer25 found no difference in attendance in childbirth classes for first-time mothers who chose discharge before or after 24 hours after birth. In another study including 540 first-time mothers, 27.6% stayed in the hospital for less than one day35. Approximately 80% of all the first-time mothers in this study received prenatal education35. However, the proportion of first-time mothers discharged within one day and received prenatal education was not reported35. Furthermore, the content of prenatal education was not described35. Prenatal education seems to have little impact on the mothers’ readiness or decision to be discharged within 24 hours. The studies all lacked a detailed description of the content of parental education.A descriptive study documented, that prenatal classes had minimal effect on the mothers’ readiness to be discharged from the hospital 24 hours after birth25. The study found that the mothers in the short-stay group reported more sources of support than the group that chose to remain in the hospital for more than 24 hours after birth25. Furthermore, the social support came specifically from the mother’s husband, mother, and mother-inlaw25. This indicates that social support from the nearest relatives might positively influence the parents' readiness for discharge within 24 hours after birth.A survey compared two groups of first-time parents who were discharged before or after 24 hours after birth29. This study found that only 4% of first-time mothers left the hospital within 24 hours after birth29. In comparison, none in the control group, that did not receive an offer of a home visit by the midwife, left the hospital within 24 hours29. The home visit by the midwife included guidance in breastfeeding and about baby care, a physical examination of the mother and baby, and dialogue about the birth and the mother’s experience29. Therefore, it seems that a follow-up strategy with one home visit by a midwife between the second and the sixth day after birth was not enough to make the parents want to leave the hospital within 24 hours after birth.One study examined the mothers’ choice of the postpartum length of stay when the mothers were offered one home visit from a midwife between the second and sixth day after birth27. They expressed a sense of confidence and praise for their accessibility to family and friends when they needed assistance27. The availability and support from relatives had a positive effect on the parents' sense of security. On the other hand, two first-time mothers felt pressure from the health professionals at the hospital to be discharged within 24 hours after birth, which generated a sense of insecurity among the parents27. Therefore, if the parents do not feel ready for discharge, it might have a negative effect on the parents' sense of security after discharge. Another study of a new home-based model of midwifery care found that 9 out of 10 first-time mothers felt safe or very safe when being discharged within 24 hours after birth28. The home-based model included a systematic follow-up strategy with a pediatrician and midwife examining the newborn and a health examination of the mother before discharge28. Furthermore, an information package regarding the mother’s and newborn’s health and breastfeeding was handed out28. After discharge, the follow-up strategy was daily telephone contact during the first week and an offer of a home visit and a hospital visit28. In a qualitative study, one first-time father reported that they wanted a healthcare professional nearby to provide a sense of security, especially at night27. Another qualitative study found that first-time parents felt safe to be discharged within 24 hours after birth when they could easily contact midwives, day and night, and know that a midwife’s home visit was planned for the day after discharge37. Therefore, healthcare professionals’ availability and frequent contact with the parents are important to the parents' sense of security, and the parents must feel ready for discharge to feel secure.A qualitative study including 10 first-time parents (7 mothers and 3 fathers) found that first-time parents were particularly dependent on their respective network of family and friends36. The first study found that first-time mothers discharged before 24 hours after birth were less likely to want information about feelings of fatigue, breastfeeding, bottle-feeding, night-feeding, and circumcision  than those who stayed longer than 24 hours after birth35. First-time mothers under 25 years and discharged within 24 hours after birth were more likely to want information on self-care items, such as getting along with their husbands and the side effects of medication. Mothers with less than high school education were more likely to want more information on most baby care topics than mothers who graduated from high school or college35. The baby-care topics included changing, breastfeeding, their baby’s schedule, calming a crying baby, and recognizing illness35. First-time mothers discharged within 24 hours after birth with low levels of social support were more likely to want information about various topics. The topics included feelings of fatigue, resuming sexual activity, getting along with their husband, night-feeding, and their baby’s schedule35.Two studies examined how the mothers prioritized their need for the information they received in pregnancy and before discharge from the hospital36. Most mothers ranked information about identifying signs and symptoms of the newborns’ illness as the most important information before discharge36. The following important areas were signs and symptoms of maternal illness, what to do if a newborn was choking on mucus, and how to know if the newborn was getting enough milk36. Of medium importance was feeding and infant care, comfort measures, uterine massage and involution, rest, and breast care36. The resumption of intercourse and frequency of perineal pad change was ranked as least important for first-time mothers36. Subjects concerning a mother’s body change were consistently ranked lower than those related to infant care and feeding, and explanations of maternal body changes were almost consistently lower ranked than practical or ‘how-to’ information about the newborn36. The two studies show that the mothers need for information differs regarding discharge time after birth, education level, age, and amount of social support. A study based on focus group interviews and interviews with couples of 21 firsttime parents discharged between 6–17 hours after birth found that some parents felt uncertain about nursing and caring for the newborn37. However, some first-time parents did not have concerns about this37. A qualitative study including three first-time fathers discharged within 24 hours after birth reported that they felt it was nice to go home but felt unprepared26. One of the fathers wanted more information before he and the mother returned home from the maternity ward26. The details about parental education or information the parents received before discharge were not described in the latter two studies mentioned above. A study explored how mothers discharged within 24 hours experienced a follow-up strategy to access an app offering online chat with the midwife30. The mothers also had access to information material via the app30. Furthermore, the app automatically sent messages with information about signs of the baby’s well-being according to the baby’s age and information about breastfeeding30. One first-time mother found it easy to get an overview of the information and said, ‘I have read it all. I also look things up that I would not ask the nurse’30. The parents who used the app reported that the app provided timely information and guidance, and the parents felt that their needs for support after discharge were met30.In the second study, 14 first-time mothers discharged within eight hours ranked the information they wanted after birth before being discharged37. However, there was also a feeling of ‘unreality’ of the newborn being there37. Another qualitative study found that home-based postnatal care is well accepted by first-time mothers leaving the hospital within 24 hours after birth28. The parents in the study were asked if they were interested in early discharge followed by home-based postnatal care28. Most of the first-time mothers had a positive postnatal care experience28. In a final study, the first-time mothers that chose to leave the hospital within 24 hours reported that a home visit significantly influenced their ability to handle the care of their newborn, benefited their mental health and their feeling of being recognized and supported29. The common denominator of the parents who were satisfied with early discharge in all the studies was that early discharge was voluntary, indicating that the parents' influence on the decision to be discharged early affects the parents' satisfaction of early discharge.A qualitative study, where early discharge was voluntary, found that first-time parents who were discharged within 24 hours after birth expressed positive feelings about freedom, self-reliance, shared responsibility, and independence30. Another qualitative study including three first-time fathers discharged within 24 hours after birth reported that these fathers found the time from birth to discharge stressful and hectic26. The fathers found that the midwives were busy, the parents spend much time waiting for the midwives, and the amount of information the parents had to receive before discharge were all factors that contributed to the feelings of stress26.First-time parents who were discharged within 24 hours with an app that send messages automatically made some first-time mothers feeling stressed when, for example, they received a message such as: ‘Now, your baby should have at least four full nappies a day’32. The group that was discharged after 48 hours did not receive a home visit, and the parents discharged within 24 hours after birth received a home visit by a midwife on the third day after birth32. A qualitative study found that breastfeeding is described by first-time mothers who are discharged within 24 hours after birth as the ‘main thing’ and important, but challenging37. Some mothers felt breastfeeding was difficult, boring and took too long, but it became easier over time37. Through breastfeeding, mothers learned to trust themselves and their newborns. Breastfeeding was described as an interaction between the mother, the newborn, the father, the midwife, and the environment37. Another qualitative study, including 12 mothers, found that breastfeeding support with emotional reassurance, promotion of positive self-efficacy and accessible breastfeeding support after early discharge were important for a mother’s breastfeeding experience and sustaining breastfeeding after early discharge33.A descriptive survey including 101 first-time parents found no difference in breastfeeding six to eight weeks postpartum for mothers who had a 24- or 48-hour length of stay after birth34. Two studies reported that the parents experienced a lack of sleep, inexperience, and insecurity from discharge to neonatal readmission31. The lack of sleep and insecurities left the fathers feeling ill-prepared, and some felt powerless31. The mothers reported that they appreciated the calmness at home but ended up worrying, experiencing breastfeeding problems and being in pain31.A retrospective cohort study including 1214545 births found that newborns of first-time parents discharged on the day of the birth had a statistically significant higher risk (OR=1.21) of readmission than newborns discharged after a one- or two-night stay in the hospitalThe purpose of this scoping review was to give an overview of existing literature that can contribute to the development of policies at the maternity wards regarding postnatal care for first-time parents. Therefore, this scoping review aimed to identify the nature and extend of the existing evidence of what effect discharge within 24 hours has on first-time parents and their newborns. Furthermore, the aim was to identify evidence of factors that can influence the outcomes of early discharge of first-time parents.Three factors that might influence the first-time parents' readiness or decision to be discharged within 24 hours after birth were examined in the studies identified in this scoping review. First, prenatal education was found to have minimal effect on the parents' readiness or decision to be discharged early. Second, social support from the nearest relatives was found to positively affect the parents' decision to leave the hospital early after discharge. Third, a followup strategy with one home visit by a midwife between the second and the sixth day did not make the parents want to leave the hospital within 24 hours after birth. Four primary outcomes were identified in this scoping review and included the parents' sense of security after discharge, the parents' satisfaction with early discharge, breastfeeding, and neonatal readmission. Factors that might influence one or more of the outcomes were parental education, social support from relatives, follow-up strategies, availability of support from healthcare professionals, and the parents' readiness for discharge.10. Between the years 1997 to 2000, approximately 15% of all people in the US did not have health insurance38. Seven of the studies were conducted in western countries and all after the year 2010. In Norway, Sweden and Denmark, the healthcare systems are tax-funded with free access to the healthcare system in pregnancy, birth, and postpartum39. The last two studies were performed in Australia in 1995 and 2020, and there has been free access to the healthcare system since 198640. Moreover, the paid maternity leave differs substantially between the countries where the included studies were conducted. Thus, in 2016, mothers in Sweden had 35 weeks paid leave after birth41. In Norway, mothers had 45 weeks paid leave, and in Denmark, mothers had 27 weeks paid leave41. In contrast, Australian mothers had eight weeks paid leave, and in the US, mothers did not have any paid leave41. All the above factors must be taken into consideration when interpreting the results of the included studies.Overall, the studies were conducted in countries with different healthcare systems, which might influence the outcomes and make it difficult to compare the results. Thus, five studies were performed in the US and were conducted between 1987 and 1997. From 1996 the Newborns’ and Mothers’ Health Protection Act ensures a hospital stay if the mothers are covered by a group health plan or individual health insurance policy25 was the only study in this review describing the criteria for early discharge in detail according to the obstetric factors. For example, it is well documented that a blood loss of over 500 mL after birth increases maternal morbidity and mortality and increases the risk of delayed breastfeeding initiation42.Furthermore, the time for discharge varied in the included studies from six hours after birth to 24 hours after birth. The different discharge times might influence the parents' satisfaction with early discharge and the information they receive before discharge. It could also influence breastfeeding incidence since the mothers that stay 24 hours receive more guidance before discharge. Therefore, it could potentially affect the neonatal readmission rate. The criteria for early discharge in the studies is another factor to consider before comparing the results. The study by Lemmer35. However, the three studies were from 1987, 1995 and 1997, and more updated research is needed to explore if the educational programs today have improved regarding preparing the parents for early discharge. One of the studies showed that the birth experience had much more impact on the mother’s decision to stay longer than 24 hours after birth. We speculate that the mother’s birth experience still needs to be considered when deciding when the parents are discharged. In conclusion, there is a need for more and updated research on improving the parents' readiness for discharge within 24 hours.Three studies identified in this scoping review concluded that parental education had minimal effect on the parents' readiness or decision to be discharged early29 found that parents offered as many home visits as the parents needed up to the fourth day after discharge, made nine out of ten mothers feel safe regarding early discharge. However, the study lacked a description of how many home visits the parents received after discharge. Furthermore, Johansson et al.29 found that only 4% of the first-time mothers chose to leave the hospital within 24 hours when they were offered one home visit, between the second and sixth day after discharge. Thus, a gap in the literature has been identified regarding the number and content of home visits the parents need to feel safe with early discharge.The maternity wards follow-up strategies might impact the parents' feelings of safety when being offered early discharge after birth. Thus, Aune et al.35, however, the studies lacked detailed descriptions that addressed this issue. Therefore, the lack of a detailed description of the content and form of the education programs makes it difficult to compare the results. A randomized controlled trial compared two parental education programs in pregnancy for first-time mothers43. There was no difference in the length of hospital stay in the random allocation of the two groups of mothers when measured on discharge before or after 48 hours after birth43. The two educational programs were similar regarding the topics, and both programs contained seven lessons, two-hours long before birth and one meeting six weeks after birth43. The lessons in the experimental group had more focus on pregnancy, birth, and early parenting as a life transition, where the control group prepared the parents for the topics as isolated events43. Furthermore, the experimental group used more group learning and fewer lectures by the facilitators than the control group43. Finally, the experimental group included activities for the parents to take home, where the control group did not have any activities to practice or discuss at home after the lessons43. The study found a significant difference between the parents' self-efficacy and perceived parenting knowledge in the two groups43. Thus indicating that the content and form of the parental education might also have a different impact on the outcomes of first-time mothers who are discharged within 24 hours. Therefore, we recommend that information about the content, form and setting of prenatal education is described in detail in future research. When healthcare professionals develop policies at the maternity wards regarding postnatal care for first-time parents, they must consider that first-time mothers under 25 years, with a low education level and little support at home, might differ in their need for information36. Only one study from 1989 examined how the mothers prioritized the information they received before discharge36. The study found a difference between first-time mothers and multiple mothers’ priorities of information that needs to be considered when the maternity wards organize the care from healthcare professionals after birth. However, more updated research of first-time parents needs for information before discharge is needed.The parents' need for parental education in pregnancy and information before discharge is also a factor that can influence the parents' sense of security. Three studies addressed the issue of prenatal education in pregnancy27. The findings correlate with other studies that showed that support primarily from the husband and the women’s mothers positively influence a first-time mother’s confidence in infant care practices, breastfeeding and satisfaction45. However, the sample size in the two studies in this scoping review was small and more research is needed regarding how mothers and fathers best can be supported after early discharge. Furthermore, research of how healthcare providers can help prepare the father or family to support the mother is warranted in the future. The first-time fathers in the study by Feenstra et al.26 reported that the time from birth to discharge was stressful, revealing a potential gap in the literature to be explored in future research. Furthermore, more knowledge about the parents' characteristics that report having a positive versus a negative experience of early discharge is needed. Knowledge of any characteristics that might predict dissatisfaction with early discharge would aid in developing policies regarding early discharge at the maternity wards in the future. Finally, healthcare professionals should prioritize continuously care in the first hours after the birth to increase the parents' satisfaction and reduce stress after early discharge. The identified studies in this scoping review provided little knowledge of the parents' satisfaction immediately after birth and before discharge. Therefore, a gap in the literature has been identified, and more research about the parents' satisfaction with the time between birth and discharge is required in the future.Overall, the parents were satisfied with early discharge when the parents influenced the decision to be discharged early. The results of two studies in this scoping review emphasize the importance of support at home on the parents' satisfaction with early discharge32 found no difference in breastfeeding incidence between two groups discharged 24 hours after birth and 48 hours after birth; the study from 1997 included 101 firsttime mothers32. However, the study lacked a sample size calculation of the numbers of first-time mothers needed in the study to detect any significant difference between the two groups. More updated studies with more power are needed in future research. Only one study examined the mothers’ breastfeeding experience after early discharge33. The study found that breastfeeding support with emotional reassurance, promotion of positive self-efficacy and accessible breastfeeding support after early discharge, were important for the mothers’ breastfeeding experience and to sustain breastfeeding after early discharge33.Discharge within 24 hours did not negatively influence breastfeeding incidence, compared to discharge after 24 hours. Furthermore, a home visit by a midwife on the third day was found to positively influence the mother’s experience of breastfeeding and the duration of breastfeeding. However, the different definitions of early discharge found in the literature can make the data ambiguous, e.g. according to breastfeeding, where we speculate that information differs for parents who are discharged within eight hours after birth compared to parents who are discharged 24 hours after birth. Little evidence was found regarding the impact early discharge has on breastfeeding incidence. Only one study by Quinn et al.34.A large retrospective cohort study found that newborns of first-time parents who were discharged on the day of birth had a 21% higher risk of being readmitted than newborns of first-time parents who were discharged laterThere was no information regarding follow-up strategies available in California at that time, making it difficult to generalize the results to other maternity wards. More updated studies are recommended in the future. No studies examined the severity of the newborns’ illness or duration of neonatal readmission when newborns were discharged early. Furthermore, no studies of maternal readmission were found, thus leaving a gap in the literature for future research.46. One-third of the first-time mothers left the hospital within 24 hours after birth46. However, the study did not clearly distinct between the mothers discharged before and after 24 hours after birth. Therefore, the study was not included in this scoping review. Postpartum depression can have profound implications in both the short- and long-term for the mother, the family, and the child’s development48. Therefore, research relating to the incidence and impact of maternity ‘blues’ and postpartum depression are essential in the future.This scoping review has identified a gap in the literature relating to maternity ‘blues’ or postpartum depression after early discharge. A study of 49 first-time mothers discharged within 48 hours after birth reported no difference in the mean depression score compared to those first-time mothers who were discharged on the third day after birthIn this scoping review, most of the identified literature focused on the mother and the newborn. Very little evidence was found focusing on the father or co-parent. Therefore, there is a gap in the literature regarding the fathers or coparents experience of early discharge. Furthermore, we have little knowledge of what information the father or co-parent needs before taking care of the new family at home, which needs to be addressed in future research. Finally, there were no studies of the fathers or co-parents incidence of depression after discharge within 24 hours after birth.15. The first review by Benahmed et al.15 found no statistical difference between early discharge in neonatal or maternal outcomes. The studies included in the review were rated as of low to very low evidence15. This review did not examine the results separately for first-time mothers and multiple mothers, making it difficult to transfer the results to first-time mothers. The other review from the Cochrane Collaboration found no statistical difference in neonatal or maternal readmission or breastfeeding incidence14. Moreover, no difference in postpartum depression was found in the Cochrane review regarding discharge time. The authors of the Cochrane review had planned subgroup analysis of firsttime mothers compared to multiple mothers but was unable to perform the sub-analysis. Furthermore, the definition of early discharge in the two reviews varied from 6 to 96 hours. Moreover, the length of the standard stay after birth also varied from 48 hours to four or more days from birth15. Thus, the above mentioned make it difficult to transfer the results to first-time parents discharged within 24 hours.Two systematic reviews in 2010 and 2017 compared early discharge with the standard length of hospital stay after the birth of healthy mothers and newbornsThis scoping review is strengthened by the rigorous methods based on prespecified criteria in protocols for scoping reviews. However, our review was limited by screening only articles available in English or Scandinavian languages. In addition, many articles were excluded from this scoping review because there was a lack of clear distinction between primiparas and multiparas, vaginal birth or caesarean section, and discharge before or after 24 hours following the birth. Therefore, there may be evidence relevant to the topic of this scoping review that has not been included. Due to the heterogeneity in methodology, terminology and assessment procedures used in the included articles, the generalization of study results is limited. Findings of this review highlight the importance of identifying factors and outcomes related to early discharge.Based on the identified evidence, the healthcare professionals need to consider how to address the problem if the parents lack social support at home to avoid adverse outcomes of early discharge when developing an early discharge policy. Furthermore, the policy should specify the potential need for more information when the mothers are under 25 years or have low educational level. The maternity wards should also prioritize for the midwives to have time to be with the parents in the first hours after birth to avoid the parents' dissatisfaction and feelings of stress before early discharge after birth. The healthcare professionals should ensure that the parents feel ready for discharge and that they have some influence on the time for discharge. Healthcare professionals should be available around the clock for firsttime parents to increase the parents' sense of security and give breastfeeding support. Finally, the early discharge policy should contain a systematic follow-up strategy. In this scoping review, we found that daily contact with healthcare professionals in the first week after discharge, one visit by the midwife on the third day after discharge supplemented with written information about the health of the mother and newborn, might be enough to make first-time parents feel secure and to support breastfeeding when first-time parents are discharged within 24 hours after birth.This scoping review has documented that there is limited evidence of the outcome and factors that influence the outcomes for first-time parents who are discharged within 24 hours after birth. More updated research is needed regarding breastfeeding incidence, the parents need for information before early discharge, and neonatal readmission. In addition, numerous gaps in the literature have been identified: 1) the fathers or co-parents experience of early discharge, 2) the fathers or co-parents need for information before early discharge, 3) the duration and severity of neonatal readmission, 4) postpartum depression of both parents, 5) a gap regarding a detailed description of the content and form of parental education in pregnancy is missing in the existing literature, and 6) the number of home visits needed for the parents to feel safe being discharged early requires more research. It is recommended that future research of the home visit after discharge is described in detail. Future studies should implement study designs that lead to stronger evidence, a clear definition of early discharge and uncomplicated birth using standardized descriptions of criteria, context, and intervention.


Images were analysed using tensor‐based morphometry and tract‐based spatial statistics. Neurodevelopment was assessed at age 18 months using the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley‐III). Infants born earlier had higher relative ventricular volume and lower relative brain volume in the deep grey matter, cerebellum and brainstem. Earlier birth was also associated with lower fractional anisotropy, higher mean, axial, and radial diffusivity in major white matter tracts. Gestational age at birth was positively associated with all Bayley‐III subscales at age 18 months. Regression models predicting outcome from gestational age at birth were significantly improved after adding neuroimaging features associated with gestational age at birth. This work adds to the body of evidence of the impact of early term birth and highlights the importance of considering the effect of gestational age at birth in future neuroimaging studies including term‐born babies.Infants born in early term (37–38 weeks gestation) experience slower neurodevelopment than those born at full term (40–41 weeks gestation). While this could be due to higher perinatal morbidity, gestational age at birth may also have a direct effect on the brain. Here we characterise brain volume and white matter correlates of gestational age at birth in healthy term‐born neonates and their relationship to later neurodevelopmental outcome using T2 and diffusion weighted MRI acquired in the neonatal period from a cohort ( Babies born in the early term period (37–38 weeks) have poorer neurodevelopment than those born at full term (40–41 weeks). We demonstrate neonatal MRI correlates of gestational age at birth in healthy term‐born babies, and their relationship to neurodevelopment at age 18 months. We find effects of gestational age at birth on brain structure, white matter microstructure, and later neurodevelopment. Data collection for the project took place in London, UK from 2015 to 2020. This project has received UK NHS research ethics committee approval , and written informed consent was obtained from parents.This study is based on a prospective sample of neonates participating in the dHCP  at the Evelina Newborn Imaging Centre, Evelina London Children's Hospital. All infants were scanned during natural sleep without sedation as previously described , b = 400 s/mm2 (64 directions); b = 1,000 s/mm2 (88 directions), b = 2,600 s/mm2 (128 directions) , using parameters: TR = 12 s, TE = 156 ms, SENSE factor 2.11  and 2.58 , acquisition resolution 0.8 × 0.8 × 1.6 mm2.3Motion‐correction and slice‐to‐volume reconstruction of T2 weighted images were carried out using a dedicated algorithm as previously described , and 10 due to visible abnormalities of possible clinical significance on MRI. This left 454 individuals included in the study. Of the 454 individuals, 374 had diffusion MRI data, 332 had T2 data and were followed up at 18 months, and 281 had T2 data, DWI data, and were followed up at 18 months. The demographic details of the cohort are summarised in Table 3.2Voxel‐wise analysis of relative brain volume using TBM showed a positive correlation of GAAB  with relative brain volume (Jacobians) in the deep grey matter , cerebellum, inferior parts of the frontal and temporal lobes, and parts of the brainstem bilaterally. The relative volumes of parts of the ventricles were negatively correlated with GAAB Figure .3.3Analysis of white matter diffusion MRI characteristics using TBSS showed that gestational age at birth was positively correlated with FA and negatively correlated with MD, AD, and RD. AD was most strongly associated with GAAB, and FA least strongly associated. Parts of the superior corona radiata and projection fibres to the precentral gyrus bilaterally were significantly associated with GAAB in all DTI modalities. The MD, AD, and RD of superior longitudinal fasciculus bilaterally were significantly associated with GAAB, although FA was not significant in this tract. The AD and RD of the corona radiata bilaterally were also significantly associated with GAAB, as was the AD of the corpus callosum Figure .3.4r2 = .04, p = .002, Motor adj. r2 = .04, p = .001, Language adj. r2 = .04, p = .001)  Figure . For eveAn exploratory analysis of the influence of the inter‐individual brain differences shown in Figures n = 332), and analyses of adding brain volume and white matter diffusion information were performed in individuals who had a T2 scan, a DWI scan and follow‐up (n = 281). Adding volume significantly improved all models (the F statistic of the model with imaging data added is significantly greater (p < .05) than the model without imaging data), whereas adding diffusion features only improved the language model  and cognitive score , although the latter of these would not survive multiple comparisons correction  also negatively correlated with Bayley‐III motor (adj. n Figure . Adding Individual volume differences appear to be more important in future neurodevelopmental outcome than diffusion differences in this cohort. This may be due to the different temporal trajectories of cortical structural development and major white matter tract myelination (Sampaio & Truwit, Our study has some limitations. The most significant of these is the mathematical difficulty of delineating the effect of GAAB on MRI appearance with the much more dominant effect of brain maturation over time, as measured by postmenstrual age at scan. In a cohort of term‐born babies scanned as soon as possible postnatally, these two variables are colinear (as is the case in our cohort, Supplementary Figure At the time of writing, all previously published studies which associated MRI findings in the neonatal period with GAAB (Broekman et al., Our study has several strengths. We have used a large homogenous cohort, which improves the quality of neuroimaging analysis and removes potential bias from abnormally low birthweights and medical complications in early term but does limit clinical translatability of our findings. We have used well established MRI analysis methods. An immediate avenue for future research would be to investigate the effect of GAAB on functional connectivity measures in the neonatal period as these have been shown to be significant in older children (Kim et al., These results are important for future neuroimaging studies. Neonatal MRI is now well established within the neuroimaging field, and an increasing number of studies focus on term‐born infants. Many of these do not include GAAB as a covariate in analyses (Feldmann et al., This work advances our understanding of the neurodevelopmental effects of birth at different gestational ages after 37 weeks. The finding of significant associations of GAAB with MRI soon after birth is important to consider in neonatal neuroimaging studies.Effects of gestational age at birth on perinatal structural brain development in healthy term born babies: Supplementary MaterialClick here for additional data file.


The association between a slower physical growth and poorer neurodevelopment has been established in infants born preterm or small for gestational age. However, this association is inconsistent in term-born infants, and detailed investigations in infancy, when intervention is most beneficial for improving outcomes, are lacking. We therefore examined this association separately by sex during the first year of life in term-born infants.Using data collected until children reached 12 months old in an ongoing prospective cohort of the Japan Environment and Children’s Study, we analyzed 44,264 boys and 42,541 girls with singleton term-birth. The exposure variables were conditional variables that disentangle linear growth from weight gain relative to linear growth, calculated from the length and weight at birth and 4, 7 and 10 months old. Neurodevelopmental delay was identified using the Japanese-translated version of Ages & Stages Questionnaires, third edition.A reduced risk of neurodevelopmental delay at 6 months old was observed in children with a higher birth weight  and increased linear growth between 0 and 4 months old . A reduced risk at 12 months was found in children with an increased linear growth between 0 and 4 months , boys with an increased relative weight gain between 0 and 4 months , and girls with a higher birth weight .These results suggest that a slow physical growth by four months old may be a predictor of neurodevelopmental delay during infancy.The online version contains supplementary material available at 10.1186/s12887-021-02815-9. Such growth-faltering infants are at high risk of poor neurodevelopmental outcomes later in life [Prenatal and postnatal growth of the body has been linked to later neurocognitive development. Growth restriction  in life , 2. In t in life –5. The a in life –14, othe in life , 16. Fur in life , 13–16 w in life , 11, 12, in life , 18.per se hampers the determination of which component is more influential. To dissociate the effects of length/height growth from those of weight growth, Adair et al. and Horta et al. used a sophisticated method of ‘conditional growth modeling’ [Most of these previous studies have separately assessed anthropometric gains in either length/height or weight between two age points (e.g. birth to six months old). As the length/height and weight are strongly correlated within an individual, assessing these indices odeling’ , 20. Thiodeling’ , 22. WitUsing a conditional growth model with a nationwide prospective cohort from the Japan Environment and Children’s Study (JECS) that includes over 100,000 children, the present study examined the relationship between physical growth and neurodevelopment separately by sex during the first year of life in term-born infants. To collect neurodevelopmental information from such a large number of children, we used a parent-reported screening tool rather than individualized face-to-face tests. During this period, neurodevelopment is difficult to assess precisely, and important changes can manifest in the individual developmental trajectory. However, a detailed investigation of this relationship during infancy is extremely important for detecting neurodevelopmental delay for early intervention.via self-reported questionnaires completed by the parents.The JECS is a nationwide, multicenter, prospective birth cohort study funded by the Ministry of Environment, Japan. The study design details have been described elsewhere , 24. In The JECS protocol was reviewed and approved by the Ministry of Environment’s Institutional Review Board for Epidemiological Studies and by the ethics committees of all participating institutions (#15000141). The ethical approval for this study was an extension of the ethical approval for the JECS protocol. Written informed consent was obtained from all parents.In this study, we used the fixed dataset “jecs-an-20180131” released in March 2018. The dataset includes all available data of 104,065 fetuses, linked to their mothers’ data, collected until children were 12 months old. As subjects, we selected 89,953 children with live singleton term birth  who had parents of Japanese nationality and complete basic information on mother’s parity, child’s sex, length and weight at birth  to birth, were obtained from medical records. Subsequent anthropometric data were all derived from the personal health record of the child. Nearly all Japanese children receive a public health checkup at four months old. Their length and weight were thus directly measured by a public health nurse or a hospital nurse and officially documented in the record. They also receive similar checkups at 7 or 10 months old, occasionally at both 7 and 10 months old, depending on residency. Parents were asked to transcribe these anthropometric data at the 4-month checkup in the 6-month questionnaire and those at the 7- and 10-month checkups in the 12-month questionnaire. Because the data were not measured at exactly 4, 7 and 10 months, the values were extrapolated from the anthropometric data at birth and those at the 4-, 7- and 10-month checkups . The extper se were treated as conditional variables at birth, as they had no previous anthropometric data to be regressed against. Consequently, our conditional variables included length and weight at birth and conditional length and relative weight at 4, 7 and/or 10 months old.These z-scored length and weight values at different ages were processed using conditional growth modeling, as in the studies conducted by Adair et al. and Horta et al. , 20 but The outcome measure was neurodevelopmental delay at 6 and 12 months old using the Japanese-translated version of the Ages & Stages Questionnaires: third edition (ASQ-3). This version was prepared through a back-translation procedure and was approved by the publisher of the original English version . The ASQThe ASQ-3 assesses five developmental domains: Communication, Gross Motor, Fine Motor, Problem Solving, and Personal-Social domains. For each domain, six skills are described to which parents answer “yes,” “sometimes,” or “not yet,” depending on whether or not their child has demonstrated the described skill. The responses are converted to points, with “yes” receiving 10 points; “sometimes”, 5 points; and “not yet”, 0 points. The child’s score for each developmental domain is the sum of all points received for the items under that domain and ranges from 0 to 60 points. The cut-off score for each domain is defined as two standard deviations below the mean score of large, standardized samples in the United States of America. A child is defined as having a neurodevelopmental delay if a score is at or below the cut-off level in any developmental domain. Although preliminary cut-off scores of the Japanese translation were recently proposed , these wTo examine which component and periods of physical growth are specifically associated with infant neurodevelopment, we conducted multivariable regression analyses using conditional variables at different ages. Because these variables are not correlated with each other, the variables and covariates were included together in the same model without concerns about collinearity . The covAll analyses were performed using the R software program, version 4.0.3 . Quasi-Poisson regression models were used to estimate adjusted relative risks (aRRs) with 95 % confidence intervals (CIs).Among the 44,264 boys and 42,541 girls eligible for the analysis, anthropometric data were available at 4 months of age in 37,136 (83.9 %) boys and 35,732 (84.0 %) girls, at 7 months in 16,231 (36.7 %) boys and 15,758 (37.0 %) girls, and at 10 months in 25,616 (57.9 %) boys and 24,570 (57.8 %) girls, respectively. Ultimately, 10,016 (22.6 %) boys and 9,801 (23.0 %) girls had complete data at all timepoints of birth, 4, 7 and 10 months of age.In these children, neurodevelopmental delay at 6 months old was observed at similar rates in boys (8.9 %) and girls (8.5 %), whereas that at 12 months old was more frequently identified in boys (16.9 %) than in girls (12.6 %). The baseline characteristics of the children who did not have all data available were comparable to those of children with complete data, but their parents tended to more often be multipara, have a smoking habit and have less education and income than those of complete-data subjects Table .Multivariable regression models revealed that a reduced risk of neurodevelopmental delay at 6 months old was found in boys with a higher birth weight  and an increased conditional length at 4 months old  Table . On analWith regard to neurodevelopmental delay at 12 months old, we first created a regression model using the data of children who had complete anthropometric data throughout the first year of age and all covariates Tables , model 1The present study investigated the relationship between physical growth and neurodevelopmental delay during the first year of life in term-born infants. As indices of physical growth, we discriminated linear growth from relative weight gain, represented as ‘conditional length’ and ‘conditional relative weight’, respectively. A reduced risk of neurodevelopmental delay at six months old was observed in boys and girls with a higher birth weight and an increased conditional length at four months old. A reduced risk of neurodevelopmental delay at 12 months old was found in boys and girls with a higher conditional length at 4 months old, boys with a relatively high conditional relative weight at 4 months old and girls with a higher birth weight. These findings indicate that children with a poor growth in early infancy are at an increased risk for neurodevelopmental delay. In contrast, conditional variables at 7 and 10 months old did not increase the risk.in utero. However, the present study included several limitations. First, the information was mainly collected via self-administered questionnaires. Although the anthropometric data were based on official records, the identified neurodevelopmental delay might be somewhat equivocal, relying on the parent-reported screening test of the Japanese version of ASQ-3. Next, a considerable proportion of children had missing information on physical growth at different time points and neurodevelopmental outcomes and were thus excluded from the analysis, possibly producing selection bias. Finally, the results of our regression analyses were not adjusted for other unmeasured confounders, including the maternal intelligent quotient, which greatly influences the neurocognitive development of offspring.This was one of the largest birth cohort studies yet conducted to examine the association between physical growth and the neurodevelopmental outcome. Our large sample size had strong statistical power and revealed subtle but significant associations. Furthermore, body sizes were converted to z-scores using domestically standardized growth curves, and the sizes at birth were further adjusted for the mother’s parity and child’s gestational age, enabling the precise estimation of the body growth We found that a higher conditional length at 4 months old was consistently associated with a reduced risk of neurodevelopmental delay at 6 and 12 months of age for both sexes. The results agree with the findings from previous studies using conditional modeling, which reported a greater impact of linear growth than relative weight gain on schooling and intelligence , 20. TheWe also found other associations between physical growth and neurodevelopmental delay during infancy. The association between a higher birth weight and a reduced risk of neurodevelopmental delay at 6 and 12 months old is concordant with the well-known finding that birth weight is a significant determinant of later neurodevelopment –49. The Using appropriate conditional modeling, we showed that poor early physical growth was associated with an increased risk of neurodevelopment delay during the first year of life in term-born infants partly in a sex-dependent manner. If a child presents with growth failure in early infancy, the infant should be monitored carefully to detect neurodevelopmental delay for early intervention. Ongoing investigations in the JECS cohort may reveal later-term outcomes.Additional file 1:


Sphenoid sinus pseudoaneurysm arising from the cavernous segment of the internal carotid artery (ICA) caused by traumatic vessel injury is rare, and rarer is a concomitant carotid-cavernous fistula (CCF). In particular, delayed subarachnoid hemorrhage (SAH) due to pseudoaneurysm rupture has not been reported to-date in literature. Here, we report a case of sphenoid sinus pseudoaneurysm with CCF presenting with delayed SAH.A 73-year-old man presented with traumatic brain injury due to motorcycle accident.Twenty-four days after admission, the patient's neurological status suddenly deteriorated. Brain computed tomography (CT) showed acute SAH along interhemispheric cisterns and suprasellar intracerebral hematoma. Brain CT angiography and digital subtraction angiography revealed giant sphenoid sinus pseudoaneurysm with CCF and the daughter sac of the pseudoaneurysm extended to the intracranial part via fracture in the superior wall of the sphenoid sinus.As the sphenoid sinus pseudoaneurysm and CCF shared one rupture point, endovascular treatment with intraarterial approach using coil and liquid embolic material by balloon assisted technique was performed simultaneously.The origin of the pseudoaneurysmal sac and CCF was sufficiently blocked after injection of liquid embolic material and the lesions completely resolved immediately after endovascular treatment.Sphenoid sinus pseudoaneurysm and CCF rarely occur following head trauma through a series of processes involving fracture of the lateral wall of the sphenoid sinus and ICA cavernous segment injury. Sphenoid sinus pseudoaneurysm may present as SAH through intracranial rupture with concomitant superior wall fracture of the sphenoid sinus. Therefore, early diagnosis using CT or magnetic resonance angiography and appropriate treatment through understanding the disease mechanism is necessary. Therefore, the main presenting symptoms are either massive epistaxis after aneurysmal rupture along the sphenoethmoidal recess – nasal cavity pathway or ophthalmic symptom caused by the mass effect.,3 Since it occurs outside the dura, the chances of subarachnoid hemorrhage (SAH) from pseudoaneurysm rupture is extremely rare and to-date, has not been reported in literature. Additionally, though sphenoid sinus pseudoaneurysm is caused by an injury to the cavernous segment of the ICA, concomitant carotid cavernous fistula (CCF) has rarely been reported.,5 Here, we report a case of sphenoid sinus pseudoaneurysm with CCF presenting with delayed SAH.Pseudoaneurysm in the sphenoid sinus caused by internal carotid artery (ICA) injury is a very rare complication of head trauma.22.1A 73-year-old man presented with traumatic brain injury due to motorcycle accident. The patient had no relevant past medical history. In the emergency room, initial Glasgow coma scale (GCS) score was 4 and his pupils were bilaterally fixed. Brain computed tomography (CT) scan showed diffuse SAH and acute subdural hematoma (SDH) in the left convexity, due to which 10 mm midline shift was observed. Cranial CT revealed multiple skull base fractures and ethmoid bone and sphenoid bone fractures. Emergency decompressive craniectomy and SDH removal were performed, after which, the patient was taken to the intensive care unit. The patient was sedated with midazolam to decrease brain metabolism and control intracranial pressure. Fourteen days after decompression, the patient regained consciousness enough for spontaneous eye opening and voluntary movement. On the 24th day, sudden neurological deterioration occurred. Follow-up brain CT revealed suprasellar intracerebral hematoma and SAH in the interhemispheric cisterns  was advanced into the sphenoid sinus pseudoaneurysm. The triple-microcatheter technique was employed to occlude the pseudoaneurysm using multiple detachable coils Fig. B. To emb2.3Seven days after embolization, GCS score of the patient recovered to 7 and pupillary responses were prompt. Follow-up brain CT angiography 14 days after the procedure showed no visible sphenoid sinus pseudoaneurysm or CCF and intact flow in the right ICA. The patient began spontaneous movement and eye opening, and was transferred to rehabilitation hospital 6 weeks after the intervention.2.4The institutional review board of approved the retrospective review of the medical records of the patient and waived the requirement for informed consent.3 Sphenoid sinus pseudoaneurysm is another disease entity caused by damage to the cavernous segment of the ICA, which is rare compared to CCF, and cases with concomitant CCF have rarely been reported.,2,7–9 Theoretically, since the segment of ICA is located in the cavernous sinus, it is difficult to understand that CCF is not accompanied with pseudoaneurysm due to vessel damage. However, anatomically, a part of the cavernous segment of the ICA contacts the lateral wall of the sphenoid sinus to form the carotid sulcus, and the boundary is separated by bones with a thickness of less than 0.5 mm in about 88% of cadaver specimens. Certainly, not all parts of the cavernous segment are nested into the carotid sulcus, and there are areas that are completely surrounded by the cavernous sinus.,11 Therefore, it is considered that two types of sphenoid sinus pseudoaneurysms occur, with and without CCF, depending on the site of the injury. In the case the injury in an area where the ICA and sphenoid sinus are in contact, sphenoid sinus pseudoaneurysm occurs without CCF. However, in the present case, it is presumed that the medial wall of the ICA was injured which spread through the fractured lateral wall of the adjacent sphenoid sinus, resulting in CCF with sphenoid sinus pseudoaneurysm (Fig. The carotid cavernous fistula is a well-known disease entity caused by vascular injury of the cavernous segment of ICA due to head trauma, and its incidence accounts for 0.2 to 0.3% of total traumatic head injury.,3,7 Rupture of pseudoaneurysm reportedly causes recurrent or massive epistaxis, to the nasal cavity through the sphenoethomoidal recess, which is route drainage of the sphenoid sinus. Moreover, extrinsic compression by the mass of the pseudoaneurysm causes ophthalmic disorders such as monocular or binocular blindness. When CCF is concomitant with sphenoid sinus pseudoaneurysm, symptoms of venous engorgement such as exophthalmos, bruit, chemosis, and vision impairment may be part of clinical manifestations of the condition. However, poor state of consciousness of the patient following severe head trauma may prevent the detection of CCF symptoms, like the present case. In our case, delayed SAH occurred due to intracranial rupture of pseudoaneurysm, which has not been reported to-date in literature. Theoretically, sphenoid sinus pseudoaneurysm arising from the cavernous segment of the ICA is extradural and does not induce SAH. However, in our case, fracture of the superior wall of the sphenoid sinus also occurred, and the pseudoaneurysm that filled the sphenoid sinus formed a daughter sac towards the fracture defect (Fig. Sphenoid sinus pseudoaneurysm have mostly been reported as a direct connection from the cavernous segment of the ICA to the sphenoid sinus.ect Fig. D and E.  Sphenoid sinus pseudoaneurysm may be treated with coils or covered stent and detachable balloon through an intraarterial approach. However, pseudoaneurysm with CCF requires more complicated treatment as both need to be resolved. Since CCF will not resolve by embolization of aneurysmal sac alone, additional embolization using an intravenous or intraarterial approach is necessary to treat CCF. Through intraarterial approach, embolization may be performed by separately selecting pseudoaneurysm and cavernous sinus. However, since they share one rupture point as with the present case, simultaneous intervention may be considered if the ICA at the origin of the pseudoaneurysmal sac and CCF is sufficiently blocked (Fig. CCF and sphenoid sinus pseudoaneurysm are commonly treated with endovascular surgery.ked Fig. D. In our4Sphenoid sinus pseudoaneurysm and CCF are rarely seen with concurrent injury of the cavernous segment of the ICA and the sphenoid sinus. In addition, SAH may occur due to pseudoaneurysm rupture through a fracture defect in the superior wall of the sphenoid sinus. Early diagnosis and prompt treatment is possible through in-depth understanding of the disease mechanism.Conceptualization: Min Jai Cho, Chi-Hoon Choi, Kyu Sun Yum, Sang-Hoon Cha, Kyung Sik Yi.Data curation: Min Jai Cho, Yook Kim, Kyung Sik Yi.Formal analysis: Min Jai Cho, Jisun Lee, Kyung Sik Yi.Supervision: Chi-Hoon Choi, Kyu Sun Yum, Sang-Hoon Cha.Writing – original draft: Min Jai Cho, Kyung Sik Yi.Writing – review & editing: Min Jai Cho, Kyung Sik Yi.