To examine the social, economic and demographic factors that determine low birth weight in the two Kassena Nankana districts of the Upper East region of Ghana.p-value of < 0.05.Cross-sectional data was collected from January 2009 to December 2011 using the Navrongo Health and Demographic Surveillance System which monitors routine health and demographic outcomes in the study area. Data on foetal characteristics such as birth weight, and sex and maternal age, parity, maternal education, marital status, ethnicity, religious affiliation and socio-economic characteristics were collected and described. Tests of means, proportions and Chi-squares are employed in bivariate analysis, and adjusted logistic regression models fitted to control for potential confounding variables. All tests were two-sided and test of significance was set at There were 8,263 live births  with an overall average birth weight of 2.85 kg . The average maternal age was 28 years, median parity 2, maternal literacy rate was about 70% and 83% of mothers were married. The prevalence of low birth weight was 13.8% 95%CI  and more in female babies than in males . Determinants of low birth-weight after controlling for confounding factors were sex of neonate , maternal age (p = 0.004), and mothers who are not married .Female neonates in this population were likely to present with low birth weight and maternal factors such as younger age, lower socio-economic status and single parenthood were major determinants of low birth weight. Effective and adequate antenatal care should therefore target women with these risk factors. Most low and middle-income countries could not meet the target for Millennium Development Goal 4 (MDG) which is reduction in childhood mortality by two-thirds between 1990 and 2015 [Birth weight is known to influence the survival and development of neonates. It refers to the first weight measurement taken of a new-born immediately after birth. Normal birth weight is essential for child survival, development and health later in life. According to the World Health Organization (WHO), Low Birth-Weight (LBW) is weight at birth that is less than 2.5 kg . Even thA number of studies have reported an association between LBW and pulmonary dysfunction, impaired physical growth, adverse neurological outcome, psycho-social development and social disadvantages –9. An asSeveral studies have reported on the determinants of LBW but these have often not focussed on socio-demographic factors . Non-seaInterventions to reduce LBW will require an understanding of the associated foetal, maternal, prevailing environmental and socio-demographic factors. There is however, limited information on this from Northern Ghana. This study examined biological and environmental factors that influence low birth weight in the coverage area of the Navrongo Health and Demographic Surveillance Site (NHDSS) in Upper East region of Ghana.The study was conducted in the Navrongo Health and Demographic Surveillance site. The area lies between latitude 10.300 and 11.100 North and longitude 1.10 West . This arThe study area has a crude birth rate of 25/1000, crude death rate of 10/1000, total fertility rate of 3.8, neonatal mortality rate of 13.4 per 1000 live births, and infant mortality rate of 32.1. Under-five mortality rate per 1000 live births is report as 60.8; life expectancy at birth is 56.4 years for males and 67 years for females .The study involved all mothers and their babies born at term (37 weeks and above) from January 2009 to December 2011 and whose parents were resident or natives of the study area. The data was collected through the NHDSS which collects and updates health and socio-demographic characteristics of all persons and households in the two Kassena-Nankana districts of the study area. This involves the regular visits to households by trained fieldworkers every 4 months to interview heads of households or an adult member of the household. Routinely collected data included pregnancies, live and stillbirths, morbidity, deaths, in-migration and out-migrations, childhood vaccinations and verbal autopsy (VAs) on all reported deaths within its operational area. In addition, information on household socio-economic characteristics is also collected.The main outcome variable for this study is birth weight which was recoded into two mutually exclusive binary outcome: low birth weight defined as birth weight < 2.5 kg and normal birth defined as birth weight ≥ 2.5 kg according to WHO recommendations . CovariaMaternal ages at delivery were calculated using the mothers’ and babies’ birthdates. Educational status was defined as either not having any form of formal education or the highest level of formal education attained. Parity refers to the number of births by a mother including the index baby and ethnicity referred to self-reported ethno-linguistic grouping the mother identifies with.All data are routinely collected using compound registration system, checked for inconsistencies and corrected before they are entered into a Foxpro database. Five per cent of all household data are randomly selected and re-entered as a quality control measure.The variables were extracted and analysed using the statistical software STATA version 12.0 SE .Descriptive statistics was used to describe the baseline maternal and new born characteristics. Categorical data are presented in proportions and the differences in socio-demographic characteristics by birth weight status examined using Pearson's Chi squared test.Determinants of LBW were examined using logistic regression analysis. Reference categories were defined as those usually associated with the lowest birth weight. Odds ratios with 95% confidence intervals are presented and factors associate with LBW are those with a p<0.05. For categorical variables with more than two categories, a post-estimation analysis was done to examine the overall significance of the variable and one p-value obtained. The variance inflation test was employed to test for multi-collinearity between related variables and variables that were found to be collinear were those with a VIF of more than 10 and these excluded from the final logistic regression model.Presented in The average maternal age was 28 years (±7.4 SD), about 11% of the mothers were teenagers, about 31% had not attained any formal education, about 23% of the mothers were in the poorest quintile and 18% in the rich quintile. 83% of the mothers were married.A large fraction of the LBW outcomes 19.8%  were from mothers in the age group 15–19 years and the least from mothers aged 35 plus 11.7% . Large proportion (20.5%) of mothers, who previously had one child, had higher LBW children compared to those who had between 2–3 children (20.5% vs 11.0%). The proportion was still high when compared with their counterparts who previously had 4 or more children (20.5% vs 11.1%). Mothers who belong to a household in the upper socio-economic class  and lower socio-economic  class had comparable proportion of birth weights, but those who were in the middle class (Average) had large proportion (16%) of low weight babies (Pearson chi2(4) = 12.2861 P-value = 0.015).An initial unadjusted bivariable analysis of the maternal and socio-demographic characteristics showed that sex of neonate, maternal age, household socio-economic status and marital status significantly influenced the birth weight of a neonate as shown in Multicollinearity was detected between maternal age and parity after performing a variance inflation test (VIF) and thus parity was not included in the adjusted logistic regression model.Factors associated with LBW from the multivariable analyses included sex of neonate, maternal age, and marital status. Female neonates had about 32% increased odds of being born with low birth weights compared to their male colleagues; .Mothers in the 20-34-year age group were less likely to have neonates with LBW compared to those below 20 years . Similarly, the odd of having LBW neonate was 35%  lower among women who were 35 years and above when compared to the under 20 years group. Socio-economic condition as measured in this study was an important risk factor for LBW as identified by other studies in similar settings ,18. Our In this study, we have examined how socio-demographic, foetal and maternal factors predict low birth weights of new-born babies in the Kassena-Nankana districts in northern Ghana. We found that the mean birth weight of babies in the study area was 2.85 ±1.0 kg with males significantly heavier than females by 0.1 kg. Our sample size was powered enough to detect small but significant difference in the birth weight of male and female babies. Some studies ,18 also Determinants of LBW in this population were maternal age, lower socio-economic status and single parenthood. Among these, maternal age constituted an important risk factor with women less than 20 years of age recording the highest proportion (19.8%) of LBW born in this study. The strong association between maternal age and birth weight is consistent with a study conducted by MacLeod and Kielyin 1988 where they found a significant progression of birth weight with advancing age of mother . SimilarBoth bivariable and multivariable analyses did not show any significant association between birth weight and educational status of the mother, this contrast studies conducted in two different political and social systems, West and East Germany. They found that mothers among the lowest category of education in both West and East Germany had an unadjusted relative risk of 2.5 for delivering an small for gestational age child compared to those of the highest education category . Both thet al. in their examination of maternal religious attendance and low birth weight in the United States where they identified maternal religious attendance to be protective against low birth weight and stated that lower rates of cigarette use help to mediate 11% of the association between religious affiliation and low birth weight. Their results further suggested that the health benefits of religious involvement have the potency to extend across generations [Both regression analyses and chi squared test did not show any association between religious affiliation of the mother and birth weight. This is contrary to Burdette erations . Howevererations ,30. Simierations . SpencerNeonatal sex is a very important risk factor identified by this study as it was highly associated in all levels of the analysis. Female neonates had 33% increased odds  of being born with LBW than their male counterparts. Manyeh (2016), found that being born female was protective against LBW in southern Ghana while Abubakari (2015) on the contrast found similar results with our study where being a male neonate was rather protective against LBW in rural Northern Ghana [, 1.51) oLBW continues to be a significant public health problem and as multiple factors are associated with it, it requires a more holistic and multipronged approach for its reduction. The concept of high-risk approach needs to be implemented which means better health care services to all antenatal subjects with special attention to those who are found to be at high risk. Early registration of pregnancy should be promoted so as to detect the presence of any high-risk factors at the earliest. Importance of regular ANC visits should be explained to each of the high-risk women so that any untoward consequences can be averted. Strengthening Information-Education-Counselling activities at health centres and/or CHPS compounds and in the community would help to a great extent. Such education must address issues like harms of early marriage, teenage pregnancy and proper nutrition during pregnancy.Female neonates in this population were likely to present with low birth weight and maternal factors such as younger age, lower socio-economic status and single parenthood were major determinants of low birth weight. Effective and adequate antenatal care should therefore target women with these risk factors.S1 Data(XLS)Click here for additional data file.S1 Table(DOCX)Click here for additional data file.


Pericardial cysts are rare mediastinal cysts composed of a single fluid-filled mesothelial layer and can be congenital in origin or develop secondary to pericarditis, trauma, or infection. Although most pericardial cysts are asymptomatic, life-threatening complications can occasionally occur. We report on a 57-year-old man with an asymptomatic 9 cm pericardial cyst that was incidentally found as an abnormal cardiac silhouette on routine chest radiography. Further imaging confirmed the presence of a pericardial cyst that was compressing the right atrium. The patient underwent successful video-assisted thoracoscopic removal of the pericardial cyst under general anesthesia. The patient's postoperative course was uneventful and he was discharged on postoperative day 1 in a stable condition. To our knowledge, this is the first report regarding the anesthetic management of a patient with a giant pericardial cyst undergoing thoracic surgery. Knowledge regarding the perioperative challenges associated with the removal of pericardial cysts can prevent complications and improve patient outcomes. Pericardial cysts are rare entities and comprise 7% of all mediastinal masses. The reported incidence of pericardial cysts is 1 in 100,000 population per year . These cThe treatment options for pericardial cysts include observation, percutaneous drainage, and surgical resection. Surgical excision is indicated for symptomatic cysts or large asymptomatic cysts given that they are associated with an increased risk of complications . PotentiThere are several case reports on patients with pericardial cysts in the literature , 5–9. HoA 57-year-old asymptomatic man with no significant past medical history was found to have an enlarged cardiac silhouette on a routine chest radiograph . Magnetiμg/kg. Neuromuscular blockade was achieved by intravenous administration of succinylcholine 1.5 mg/kg. Ephedrine 0.1 mg/kg was administered following induction to minimize the hemodynamic effects of the induction agents and positive pressure ventilation. A 37-French left-sided double-lumen endobronchial tube (DLT) was placed. The patient was placed in the left lateral decubitus position. Anesthesia was maintained with oxygen (fraction of inspired oxygen of 0.6), air, and sevoflurane . The right lung was collapsed and neuromuscular blockade was induced with rocuronium 0.6 mg/kg. A 1-cm incision was made in the posterior axillary line at the fifth intercostal space. A metal port was placed and a 10-mm, 30° thoracoscope was placed through the incision. A 2-cm incision was made above the fifth intercostal space at the mid axillary line to access the cyst. The pericardial cyst was found to be firm, and had some calcifications on the surface . A left radial arterial line and two large-bore intravenous catheters were placed. The patient was adequately hydrated with intravenous administration of normal saline. He was transferred to the operating room and placed in the supine position on the operating table. The standard American Society of Anesthesiologists monitors were placed on the patient. The pericardial cyst did not compress the patient's right bronchus or the SVC, and therefore, he was able to tolerate the supine position with no shortness of breath or hemodynamic instability. The patient was preoxygenated and general anesthesia was induced by slow intravenous administration of etomidate 0.2 mg/kg and fentanyl 1  Figures . The cys Figures . The patMRI is considered to be the best modality for the diagnosis and follow-up of a pericardial cyst because it provides excellent delineation of the pericardial anatomy and can aid in the precise localization and characterization of various pericardial lesions. It has higher accuracy than computed tomography for distinguishing malignant tissues from nonmalignant fluid-filled cysts . PericarIt is important for anesthesiologists to understand the physiological alterations caused by the presence of a giant pericardial cyst, given that they may have to anesthetize patients with this rare cyst.Some reports have demonstrated an association between a pericardial cyst and ADPKD. Given the progressive impairment of renal function in patients suffering from ADPKD, it is imperative to assess kidney function in patients with pericardial cysts who are suspected of having ADPKD before surgery . AlthougA pericardial cyst may cause significant compression of the SVC and right atrium and lead to a reduction of preload and cardiac output . This nePatient positioning can be challenging. Semirecumbent or sitting positions can prevent an increase in intracranial pressure in a patient with compression of the SVC. Orthopnea or a sudden decrease in oxygen saturation following patient positioning is suggestive of airway obstruction . WheneveHypotension may occur during induction in response to decreased systemic vascular resistance with a fixed cardiac output or venodilatation. Hypotension is further exacerbated if the right atrium or right ventricles are compressed by the pericardial cyst. Hence, drugs that cause venodilatation or a fall in systemic vascular resistance should be used with caution. Ketamine can be used safely as an induction agent due to its sympathomimetic properties . We usedSupraventricular arrhythmias, such as atrial fibrillation, are not uncommon in patients with a pericardial cyst . InteresErosion of the right ventricular wall and SVC by a pericardial cyst has been reported , 17, 24.Excision of large pericardial cysts can be very challenging. In our case, the cyst fluid was aspirated to help the surgeon with the excision . HoweverThe morbidity and mortality risks following pericardial cyst excision are very low. There is no report of complications during tracheal extubation. All reported cases were extubated following surgery with no complications in the postanesthesia care unit. In the case of video-assisted thoracoscopic cyst excision, pain control can be achieved using acetaminophen, nonsteroidal anti-inflammatory drugs or intravenous opioids. Thoracic epidural analgesia may be required when thoracotomies are performed. Thoracic paravertebral nerve block and serratus anterior plane block can also be used for the purpose of pain control , 29.Atrial fibrillation following thoracic surgery is not uncommon. It is important to rectify all triggering factors . HypoxiaIt is very important that anesthesiologists be aware of the perioperative challenges associated with pericardial cysts. This knowledge can prevent complications and improve patient outcomes.


Pregnancy after kidney transplantation has been considered as high risk for maternal and fetal complications. After careful patient selection successful pregnancies are described. Little is known about fetal outcomes and data is particularly scarce on childrens´ early development up to two years when born to kidney/−pancreas transplant recipients.Here, we analyzed maternal and fetal risk and evaluated graft function during pregnancy in transplanted women. We aimed to identify factors affecting the outcomes of mothers and their grafts during pregnancy and of children up to 2 years after delivery/ birth.All consecutive pregnancies in kidney/ kidney-pancreas recipients with live-born children from 2002 to 2016 were evaluated in two transplant centers (Charité Berlin/ University Tuebingen). All data was gathered from medical records. Impact of pregnancy on obstetrical risks, graft function and fetal development was evaluated. Additionally, for the first time development of children, including physical examination and assessment of neurological function were evaluated at 12 and 24 months.Thirty-two pregnancies in 28 patients with a median duration of 34 gestational weeks  were analyzed. 13 patients (46.4%) developed deterioration of kidney graft function > 10 ml/min during pregnancy. In majority, caesarean section was performed (75%). Twenty-five (78.1%) children were born prematurely, thereof (16%) < 28 weeks. Almost 70% had low birth weights (LBW) (< 2.500 g); median birth weight was 2.030 g. General health and physical constitution of children were unremarkable with normal development in 94% at 12 and 24 months of corrected age, respectively.Despite the high rate of preterm birth and LBW, development up to two years was age-appropriate in this cohort. Due to low absolute numbers, increasing efforts in centralized counseling, diagnostics and committed specialist support are required. Decisive treatment of these high-risk patients in specialized units leading to better performance of these patients (mother/ fetus) is deemed superior. In order to confirm this, prospective studies on neonatal and pediatric outcomes with a standard-of-care comparator arm will be conducted. There is an increasing number of positive reports on (successful) pregnancies in kidney transplant recipients –5. NeverIt was recently shown in a cohort of 56 female transplant recipients that adequate graft function (creatinine < 110 μmol/l) was positively correlated with pregnancy-related complications such as preeclampsia and preterm delivery .Prematurity is associated with several acute and chronic complications including respiratory distress syndrome, intracranial hemorrhage, apnoea, retinopathy of prematurity, seizures, necrotizing enterocolitis and temperature instability . These iInterestingly, data on children’s early development in pregnancies after kidney transplantation are scarce even though many reports on successful pregnancies in kidney transplant recipients are available –8. Even The aim of this multi-center study was to evaluate pregnancies following kidney transplantation and their impact on mother, graft and fetus/ early childhood with observation up to 2 years after delivery.From January 1st 2002 through 31th December 2016, we evaluated retrospectively all 28 consecutive patients with pregnancy and delivery after kidney or simultaneous kidney-pancreas transplantation at University Hospital Tuebingen and Charité University Berlin. Only pregnancies resulting in birth > 23 weeks of gestation were included.Mycophenolate (MPA) was routinely used for rejection prophylaxis in both centers since 1996. MPA was routinely discontinued at least 4 weeks prior to planned pregnancy and replaced by steroids or azathioprine, respectively. The decision to either steroids or azathioprine was left at discretion of the treating physician.After confirmation of pregnancy clinical parameters were recorded at regular intervals by department of gynecology and nephrology. The following characteristics were analyzed: age at transplantation/ delivery, kidney function pre- pregnancy/ at one and six months/ at one year and up to two years after delivery were gathered. Pre-pregnancy creatinine was defined as the latest result within three months before pregnancy. Glomerular filtration rate (GFR) was calculated according to the 2009 Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation . Time inTo determine the association between outcomes and the interval between kidney transplant and pregnancy, we defined the following groups: <two years versus two to five years versus more than 5 years.Additionally, physical and psychomotor development of the children in our cohort up to 2 years were examined by a pediatrician. Specifically, neonatal outcome was observed, including birth weight, gestational age, intrauterine growth restriction, APGAR -score , malformation. In order to achieve age-related variables, corrected age based on expected date of birth in preterm deliveries was used. Data were collected from the patient’s medical records. Weight was measured with an electronic scale accurate to the nearest 1 g. Length was measured with an infant-length board to the nearest 1 mm when the weight was > 1.000 g or with a nonstretch measuring tape for very preterm infants in a closed incubator. Head circumference was measured in the largest frontooccipital plane to the nearest 1 mm with a nonstretch measuring tape. Weight, length and head circumference were converted to age-specific and gender-specific Z-scores according to the WHO growth chart using calculator (Anthro software).Additionally, all mothers after live birth were asked to complete a questionnaire on their childrens’ physical developmental status. The questionnaire contained physical examination, anthropometric measures, medical and paramedical history. These findings were derived from medical examination by the pediatrician. It was complemented by regular pediatric exams of functions and abilities at 12 and 24 months (± 2 months) the results of which were reported within the questionnaires.Neonates were categorized according to World Health Organization defined as extreme premature (< 28 weeks of gestation), very preterm (28–32 weeks) and moderate-to-late preterm (32–37 weeks) . They weBased on gestational age, percentile values for birth weight, birth length and head circumference for girls and boys were calculated according to Voigt et al. . Neonatap < 0.05 were considered as statistically significant.Data are reported as mean (standard deviation) or median [interquartile range (IQR)] for skewed data. All statistical analyses were performed using SPSS version 25 . Continuous variables were compared using Student t-test. Graft and patient survival were analyzed by Kaplan-Meier analysis. Values of .Over the 14-year period 28 women had 32 pregnancies  resulting in 32 live births, including five women (17.8%) who had two live births) after transplantation, 65.6% of pregnancies occurred > 5 years after transplantation. Hypertension was present in 67.8% of women before pregnancy. Immunosuppressive regimens for the 32 pregnancies are shown in Fig. 1. Maintenance immunosuppression consisted of calcineurin-inhibitor (tacrolimus (n = 20) or Cyclosporine A (n = 6)) and steroids as dual therapy in majority of pregnancies . Three women received triple immunosuppression in combination with azathioprine . 78.2% of children (n = 25) were born prematurely, thereof four (12.5%) were born < 28 weeks because of maternal infection or early contractions . Gestational diabetes was detected in 2 cases  developed preeclampsia resulting in caesarean section at a minimum of 26(CKD-EPI) 57 ml/min/1.73m2 in median , respectively (Table (CKD-EPI) was significantly lower ((49 ml/min/1.73m2), IQR 37, 59 ml/min/1.73m2, p = .005) compared to pre-pregnancy values  was 48 ml/min/1.73m2 . One year after delivery and at last follow-up median GFR (CKD-EPI) remained lower compared to pre-pregnancy levels 50 ml/min/1.73m2 . GFR (CKD-EPI) at 24 months after delivery was lower than the all other GFR (CKD-EPI) values at delivery, and at 12 months after delivery there was no significant difference (Table Creatinine before pregnancy was 1.2 mg/dl in median (range 0.6–3.1) and GFR (CKD-EPI) of approximately 17 ml/min. This patient experienced graft loss at one month after delivery corresponding to 9.3 years after transplantation. The kidney biopsy showed severe interstitial fibrosis, tubular atrophy and severe vascular damage. 14 months later she received a second transplant from her mother. The other patient experienced graft loss 12 months after delivery (6.1 years after transplantation), resulting in chronic graft nephropathy and thrombotic microangiopathy in the kidney biopsy.Two graft losses were observed within one year after delivery, that occurred at intervals of one and 12 months, respectively Table . Resulti4/7, 322/7 and 340/7 weeks of gestational age, respectively. Both, pancreas and kidney graft function were stable during pregnancy and at the follow-ups 13, 90 and 139 months after delivery and at 85 and 163 months after kidney-pancreas transplantation. Overall, GFR (CKD-EPI) at two years was still worse than at date of delivery with lowest values collected at 6 months.Two patients after kidney-pancreas transplantation delivered three babies. They were delivered by caesarean section due to FGR at 30n = 25) were born prematurely (78.2%) and the gestational age was 34.7 weeks in median  was accounted for 53.1% of births; 21.8% were born > 37 gestational weeks. Characteristics of children are shown in Table 5/7 weeks). Birth weight was 2.030 g in median  had a cord blood gas within a normal pH (> 7.2) range Table . 25% hadResponse rate´ was 92.8%., Table Evaluation of anthropometric measures 12 and 24 months after birth, subdivided in preterm and term at delivery, is shown in Table 5Differences tended to decrease after 12 and even 24 months of age in mean weight-for age, length-for-age and head circumference-for-age z-score Table .Fig. 4aThe following abnormalities were observed at birth: microcephaly, microsomia and cryptorchism in one child and one child presented with strabism and bronchial asthma. The physical exam was normal in 93.75% (30/32) at 12 months and in 95.2% (20/21) at 24 months. In two very prematurely born children, mild neurological deviations were noted at one year of age, muscle tone disturbances in lower limbs and slightly reduced muscle tone in lower limbs, respectively. The respective findings had decreased in severity at 24 months of age. Noteworthy, their deficiencies were clearly found to have improved after two years of age. This was documented in the children’s medical records and was confirmed by neurological examination.It is well recognized that risk of maternal and neonatal pregnancy-related complications in women having undergone kidney transplant is significantly increased when compared to general population . Our stu0/7–366/7 gestational weeks) births were observed due to acute pregnancy-related causes such as acute placental insufficiency, severe preeclampsia, intrauterine growth restriction with abnormal fetal heart rate tracing, infections like chorioamnionitis or deteriorating kidney graft function.In our series, prematurity rate of 78% was higher compared to previous reports with incidences between 45 and 56% –5, 7 and0/7–366/7gestational weeks) are at a higher risk for mortality and impaired neurodevelopmental outcomes such as cerebral palsy, mental retardation as well as more behavioral abnormalities than term-born children [Generally, preterm children, even if being late preterm  infants in our series, at 12 and 24 months all children had both adequate weight and height for age. This confirms results from a first large prospective controlled study in children born to transplant recipients  but is iIn our study, we acquired data until the age of two years, when the weight and height as well as head circumference differences compared to general population had decreased over time. Only one child was still small for age Fig. a-c. We oIn accordance to the report of Sibanda et al. , the ratOptimal timing might affect the outcomes of pregnancy, the maternal graft function and maternal comorbidities. We could show that premature birth rate, low birth weight and caesarean section rate were lower in the current study in pregnancies between two and five years after transplantation. A recent retrospective study of 729 pregnancies revealed an increased risk of graft loss during the first and second year after transplantation whereas pregnancy in the third year was no longer associated with an increased graft failure rate . In accoIt still needs to be confirmed, whether our data suggesting increasing incidences of prematurity, low birthweight, caesarean section and preeclampsia in the group of women with an interval of > five years from transplant can be generalized. Interestingly, a recent report showed a high rate of preeclampsia but no association with long-term renal dysfunction .In our analysis childrens´ development was followed up to the age of two years. However due to prolonged in utero exposure to a large variety of immunosuppressants, adverse effects occurring much later cannot be fully excluded. Specifically, cardiovascular and renal disease might be of importance , 28. To Taken together, in this complicated situation with multiple underlying factors affecting maternal and fetal outcome these data indicate an encouraging outcome provided that strict controls in close intervals be performed. The impact of sustained deterioration of kidney function following pregnancy requires further research.Pregnancies following kidney or kidney-pancreas transplantation are associated with a significant rate of prematurity and low birth weight babies and should therefore be considered as “high risk”. Development of the children up to 2 years after birth was found to be good and age-appropriate in our study. Affected women should be managed in tertiary care obstetrics centers working in a tight multidisciplinary cooperation with transplant physicians, i.e. nephrologists, diabetologists, and neonatologists. We are currently setting up a nationwide registry for pregnancy following solid organ transplantation to prospectively evaluate future cases. This may help to improve performance and outcome of both mother and their children.


Nickel-containing enzymes are diverse in terms of function and active site structure. In many cases, the biosynthesis of the active site depends on accessory proteins which transport and insert the Ni ion. We review and discuss the literature related to the maturation of carbon monoxide dehydrogenases (CODH) which bear a nickel-containing active site consisting of a [Ni–4Fe–4S] center called the C-cluster. The maturation of this center has been much less studied than that of other nickel-containing enzymes such as urease and NiFe hydrogenase. Several proteins present in certain CODH operons, including the nickel-binding proteins CooT and CooJ, still have unclear functions. We question the conception that the maturation of all CODH depends on the accessory protein CooC described as essential for nickel insertion into the active site. The available literature reveals biological variations in CODH active site biosynthesis. Nine nickel-containing enzymes have been discovered and characterized so far, but there exists certainly others , 2. AmonAlthough the insertion of Ni seems spontaneous in glyoxylase I and acireductone dioxygenase, it requires dedicated biological machineries in the other cases. The present review focuses on the carbon monoxide dehydrogenases from anaerobic microorganisms (Ni-containing CODH) which catalyze the reversible oxidation of CO with high turnover frequencies –6. These2 by these microorganisms is catalyzed by carbon monoxide dehydrogenases (CODH). Nevertheless, CODH from aerobic and anaerobic bacteria are not phylogenetically related and have distinct structures and kinetic properties. Most aerobic CO-utilizing bacteria (carboxydotrophs) oxidize CO in their respiratory chain , called the C-cluster. This cluster consists of a Ni–3Fe–4S] cubane connected to a unique iron site through a linking sulfide Fig. e 7–9]. –9. 7–9].Fe–4S cubunctions . CODH ofRhodospirillum rubrum (Rr), CO can be used as an alternative to light as a source of energy  cluster at the interface of the two monomers . First, Surprisingly, whereas the maturation of some CODH is strictly dependent on the presence of one or several maturases, other CODH can be fully matured in the absence of any specific accessory protein.cooC copy but the CODH-I and III operons do) or that their maturation is not assisted by any accessory protein . So. SoE. conase Coo , 49. ItsHelicobacter pylori, it is well known that Ni–Fe hydrogenase accessory proteins can maturate another nickel enzyme, urease. Deletions of hypA and hypB cause a decrease in urease activity  compared to the wild-type strain [H. pylori [H. pylori cannot maturate Ni–Fe hydrogenase [Regarding heterologous expression, another hypothesis is that accessory proteins of other Ni-containing enzymes, such as Ni–Fe hydrogenases, from the heterologous host may be involved in the maturation of CODH , 48. In e strain . Site-di. pylori , 52. On rogenase , 54. Simrogenase . AlthougcooC gene, which definitely establishes that CODH maturation can be CooC-independent. It is so in C. acetobutylicum, whose gene CA_C0116 is annotated as a CODH and codes for a protein that has all amino acids known to be essential for CODH function (this is unlike the CA_C2498 gene which is annotated as a CODH but lacks one cysteine residue of the C-cluster and probably codes for a hybrid cluster protein). Preliminary results in our group show that indeed, expression of CA_C0116 in the absence of any CooC leads to a functional CODH.Last, we note that there are also examples of genomes that contain a CODH but no Although small in numbers, Ni-containing enzymes exhibit a remarkable diversity in terms of active site architecture and catalytic properties. They are often involved in crucial metabolic pathways, catalyzing reactions related to carbon fixation, energy conversion or pathogenicity in many microorganisms. The structure of the active site of some of these enzymes is so elaborated that accessory proteins are necessary to bind the Ni ion and insert it. This is the case for NiFe hydrogenase, urease, lactate racemase and methyl-coM reductase –58. As a


In piezoelectric semiconductors, electric fields drive carriers into motion/redistribution, and in turn the carrier motion/redistribution has an opposite effect on the electric field itself. Thus, carrier drift in a piezoelectric semiconducting structure is essentially nonlinear unless the induced fluctuation of carrier concentration is very small. In this paper, the nonlinear governing equation of carrier concentration was established by coupling both piezoelectric effect and semiconduction. A nonlinear carrier-drift effect on the performance of a ZnO nanogenerator was investigated in detail and it was elucidated that carrier motion/redistribution occurs in the ZnO nanowire (ZNW) cross section while there is no carrier motion in the axial direction. At the same time, we noted that the amplitude of boundary electric charge grows with increasing deformation, but the peaks of boundary electric charge do not appear at the cross-section endpoints. Thus, in order to effectively improve the performance of the ZNW nanogenerator, the effect of electrode configuration on the piezoelectric potential difference and output power was analyzed in detail. The electrode size for the optimal performance of a ZnO nanowire generator was proposed. This analysis that couples electromechanical fields and carrier concentration as a whole has some referential significance to piezotronics. An acoustic wave propagating in piezoelectric semiconductors usually stimulates electric fields that bring charge carriers into motion, and conversely, the carrier motion will produce an opposite effect on the electric fields and the acoustic wave itself –4. This c-axis except near the end regions, and carrier motion/redistribution is proven to occur along the cross section. Because the semiconduction in ZNWs results in some electric leakage, a smaller initial carrier concentration is suggested to be more proper for energy-harvesting from a bent ZNW , Σi(0) is the initial intrinsic energy level, which is constant in the whole cross section under P = 0. When the ZNW is bent by a nonzero end force P, Σi becomes alterable in the cross section in terms of the electric potential field, which turns where P = 50, 60, 70 and 80 nN, which can also be obtained directly from , all n-type carriers in the cross section obtain additional electric potential energy, . This potential energy increases/reduces the energy of electrons there, and thus, increases/decreases the number of the n-type carriers according to .x2-direction, and the maximal electric potential difference is between the two endpoints of the x2-axis. Furthermore, the maximal positive potential amplitude is much lower than the maximal negative potential amplitude. In a bent piezoelectric semiconducting beam, two shear deformations produce two in-plane electric field components, E1 and E2. E1 is induced by the shear strain S5 in the x1–x3 plane and E2 is induced by the shear strain S4 in the x2–x3 plane. When P acts along the x2-direction, σ5(τ13) is very small, and so is S5. Thus, both σ5 and S5 produce negligible influence on electric field, carrier concentration and electric potential. S4 is the primary deformation component to induce the electric field E2 and carrier redistribution. We show in n0 on E2 in order to understand why the maximal positive potential amplitude is much less than the maximal negative potential amplitude [E2 induced only by the piezoelectric effect of a ZNW without taking into account semiconduction (marked as “piezo” in the following figures). Independently of the deformation, in a piezoelectric insulator ZNW (without semiconduction) its Fermi energy level is always at the center of the forbidden band. Hence, the electric field E2 induced only by the piezoelectric characteristics is symmetrical with regard to the neutral axis, as shown in E2 drives the carriers upwards, i.e., the bottom portion, , loses carriers and the upper portion, , accumulates carriers. This motion/redistribution of carriers will in turn decrease the positive electric field E2. Moreover, E2 is reduced more at  than at . It can be found from  occurs at  ≈ −0.236, −0.273, −0.309 and −0.338 for P = 50, 60, 70 and 80 nN, respectively, with n0 = 1.0·1023 m−3. It should be noted that at ,  and the intrinsic energy level is Σi(0). Because  is reduced more in the region  than in , as shown in  becomes much smaller than the amplitude of the negative electric potential at . For example, for P = 80 nN, the maximal positive electric potential at  is about 0.05 V and the maximal negative potential at  is about 0.3 V, which is in agreement with the experimental results described on page 36 of [It follows from mplitude . For comn0/n′ with n′ = 1·1020 m−3. n0 on the output voltage  between the two endpoints of the x2-axis of a bent ZNW cross section for P = 50, 60, 70 and 80 nN, respectively. We have included in We now introduce η = n0 = 1·1023 m−3. The boundary electric potential reaches the minimum and the maximum at θ = π/2 and θ = 3π/2, respectively, which indicates that the maximal electric potential difference Vout occurs between the endpoints at top and bottom. Furthermore, Vout increases with increasing P. P, the maximal boundary electric displacement does no longer appear at the upper endpoint of the x2-axis. Instead, there are two peaks in the region π < θ < 2π with a certain angular deviation from the endpoint. The appearance of this phenomenon is due to the excessive nonlinear accumulation of carriers in the upper part of the cross section. The boundary charge is quite large between these two peaks and should be collected. Thus, the design of an effective electrode configuration becomes a significant issue in order to improve the output of a ZnO nanogenerator.Qe at the electrode can be obtained [Dr over the distributed surface 3π/2 − γ < θ < 3π/2 + γ,Consider the electrode configuration in the inset of obtained –43 throu, which indicates that the output current Ie for a harmonic vibration is directly proportional to the amplitude of the boundary electric charge Qe. Thus, for convenience we define the quantity W,The current flowing through this electrode is  stands for the electric potential difference between the two electrodes and θ0 = γ + 3π/2. W as a function of , with . With P changing from 30 to 80 nN, the peak point of W moves from θ0 = 1.72π ( ≈ 40°) to θ0 = 1.77π ( ≈ 49°). Obviously, a flare angle of 2 ≈ 98° of the two electrodes is suitable for all loadings below 80 nN. This electrode configuration provides an optimal output of the nanogenerator.which is directly proportional to the output power of the ZNW generator. n0 = 1·1022, 1·1023 and 1·1024 m−3. Obviously, a smaller initial carrier concentration is corresponding to a higher energy harvest. It is readily understood that semiconduction results in some electric leakage, and thus reduces the output power. For different initial carrier concentrations, electrode configurations with flare angles of 2 ≈ 88°, 98° and 88° are suitable for a ZNW generator with n0 = 1·1022, 1·1023 and 1·1024 m−3, respectively.In addition, we show the effect of the initial carrier concentration on the optimal electrode configuration in Nonlinear solutions for carrier concentration, electric field and electric potential in a bent ZNW are obtained without the assumption of small fluctuations of carrier concentration. As the bending deformation increases, carriers are gradually accumulated in the stretched portion of the ZNW, and the boundary charge is greatly increased. It is found that the electrode configuration will have a large influence on the output performance of a bent ZNW generator. Thus it is of significance to design an electrode configuration for an optimal output. Both the analysis technique and the obtained results are useful in the design of piezotronics and piezo-phototropic devices and the corresponding applications.


A growing number of studies observe associations between the amount of green space around a mother’s home and positive birth outcomes; however, the robustness of this association and potential pathways of action remain unclear.To examine associations between mother’s residential green space and term birth weight within the Canadian Healthy Infant Longitudinal Development (CHILD) study and examine specific hypothesized pathways.We examined 2510 births located in Vancouver, Edmonton, Winnipeg, and Toronto Canada. Green space was estimated around mother’s residences during pregnancy using Landsat 30 m normalized difference vegetation index (NDVI). We examined hypothesized pathways of: (1) reduction of environmental exposure; (2) built environment features promoting physical activity; (3) psychosocial conditions; and (4) psychological influences. Linear regression was used to assess associations between green space and term birth weight adjusting first for a comprehensive set of confounding factors and then incrementally for pathway variables.Fully adjusted models showed non-statistically significant increases in term birth weight with increasing green space. For example, a 0.1 increase in NDVI within 500 m was associated with a 21.5 g  increase in term birth weight. Associations varied by city and were most robust for high-density locations. For the two largest cities (Vancouver and Toronto), we observed an increase in birth weight of 41.2 g  for a 0.1 increase in NDVI within 500 m. We did not observe substantial reductions in the green space effect on birth weight when adjusting for pathway variables.Our results highlight the need to further characterize the interactions between green space, urban density and climate related factors as well as the pathways linking residential green space to birth outcomes. Proximity to green spaces has been linked to positive health outcomes. An increased amount of green space around a woman’s home during pregnancy has been associated with a reduced risk of delivering a baby that is small for gestational age , lower r2 air pollution [Most green space and birth outcome studies have not been able to comprehensively examine these hypothesized pathways. For example, a study by our group in Vancouver, Canada was able to examine air pollution, walkability and proximity to parks and found that the addition of these variables did not affect the associations between green space and birth weight . In a laollution . While sollution , 10, dir2 and particulate matter (PM10) [Indirect evidence remains important as it provides support for the potential pathways of influence linking green space to birth outcomes. For instance, motor vehicle transportation not only produces air pollutants and noise, but also changes urban form  and access to natural environment and green spaces. Thus, while high levels of exposure to ambient air pollution during pregnancy have been shown to be associated with low birth weight –14, veger PM10) . A growir (PM10) –19 and tr (PM10) –22. Morer (PM10) , 23. Parr (PM10) –26, whicr (PM10) , 28. In  . A growr (PM10) . These iwww.childstudy.ca), to examine associations between mother’s residential green space during pregnancy and term birth weight across four Canadian urban areas . Given the detailed information collected in CHILD we were able to adjust for multiple potential confounding factors and evaluate a comprehensive set of hypothesized pathways. This study provides the first opportunity to broadly examine how urban green space may influence term birth weight.We leveraged the Canadian Healthy Infant Longitudinal Development (CHILD) study  from 2009 to 2012. After excluding 83 children who were ineligible at birth and 45 families who failed to begin the study, we further restricted our analyses to mothers living in metropolitan areas and with complete residential history and covariate data. Our final sample size included 2510 births. Detailed data collection methods and characteristics of the CHILD Study have been previously described , 31. BriWe measured green space exposure using the average of Landsat 5 30 m normalized difference vegetation index (NDVI) around mothers’ residential addresses during the 9 months of pregnancy. A time-weighted average from all addresses during pregnancy (11.5% of participants moved) was computed for different buffer distances  around addresses since there is no consensus as to what buffer radius is most representative of green space exposures . NDVI isWe examined four general pathways that are hypothesized to link green space to birth outcomes. These include: (1) the reduction of harmful environmental exposures, particularly air pollution and noise; (2) providing space for increased utilitarian and recreational physical activity; (3) providing a setting for positive psychosocial influences; and (4) through directly reducing psychological stress and depression .2), fine particulate matter (PM2.5), and Ozone (O3) air pollution in our analyses. NO2 is of primary interest since this pollutant demonstrates fine-scale spatial variability that is most likely influenced by residential green space levels [2, which includes satellite NO2 estimates and land use variables [2 around major roadways, explained 73% of the variation in annual 2006 national air quality monitoring network measurements of NO2. We adjusted these estimates based on ground-level annual average measurements of NO2 to match pregnancy years. PM2.5 air pollution was assessed using 2010–2013 satellite data at an approximate resolution of 1 × 1 km fused with a chemical transport model and available ground level PM2.5 monitoring data [x System (CHRONOS) operational regional air quality forecast model at an approximate 21 × 21 km resolution [We included Nitrogen Dioxide  propagation model was used to derive residential noise estimates. Inputs to the model included traffic data , railway data , aircraft data and building heights and footprints. The creation and evaluation of this model has been described previously . In Toro® was used to represent neighborhood walkability. The walkability measure is a proprietary measure that is based on the distance to nearby places, block length and pedestrian friendliness, ranging from 0 to 100, with higher values reflecting high walkable neighborhoods in which daily errands would not require a vehicle .Park proximity and neighborhood walkability may link green space, mother’s physical activity and birth outcomes. We used a dichotomous variable for distance to park (residing less than or more than 400 m) since residents living closer to a park are more likely to use the park for physical activity , 39. WalSocial support was measured using the validated 4-item Interpersonal Support Evaluation List-12 (ISEL-12), a measure of perceived social support . This suParticipants answered questions about self-reported experienced stress using the Perceived Stress Scale (PSS) , which iParticipants also answered questions regarding depression using the 20 item Center for Epidemiologic Studies Depression Scale Revised (CESD-R) . The ranA comprehensive set of covariates were available at the individual and neighborhood level to control for potential confounding factors. Individual socio-demographic covariates collected from the study questionnaires include: maternal age; mother and father’s education ; mother and father’s race ; and household income . Pregnancy data included parity (first birth or not); smoking during pregnancy (yes/no); and month and year of birth. An indoor air quality index was also included that estimates the total exposure to multiple oxidizing chemicals in the home, which provides a more complete assessment of multiple indoor exposures linked to inflammation .2) were also included at the census tract level for the 2011 census and linked to each birth. Variables included percent white; percent adult population without a high school diploma; median household income; percentage of the population below the poverty line; and percent unemployment. Population density (coded into quintiles) was used to control for potential confounding factors associated with urban form, such as inner city cores or suburban areas. We also derived a proximity to water  variable (residing less than or more than 500 m) to control for blue-space related influences that have been identified in other research [Neighborhood SES variables and population density , physical activity , psychosocial influences , and psychological influences .We evaluated the associations between mother’s residential green space exposure during pregnancy and term birth weight, and examined the following pathways: environmental exposures  adjusting for a comprehensive set of individual and neighborhood confounding factors. The fully adjusted model includes all individual and neighborhood variables summarized previously. Associations between NDVI and birth weight are presented corresponding to a 0.1 unit increase in NDVI. We also ran overall models stratified by individual and contextual level variables selected a priori to examine potential effect modification and evaluate residual confounding.2, PM2.5, O3, Walkscore®, park and water proximity, social support and maternal stress and depression. Incremental models were then run that included each hypothesized pathway variable(s) separately and then all pathways together. Each model was adjusted for potential confounding factors included in the overall adjusted model.Next, we examined hypothesized pathways using incremental analyses. We used linear regression to examine the associations between green space and NOSeveral sensitivity analyses were conducted to examine the robustness of our models. We explored city-specific models as cities had large differences in terms of size/density, climate, and green space characteristics. Vancouver and Toronto also had available noise models and sensitivity analyses were conducted to examine how the NDVI and birth weight associations changed in these cities once noise exposures were included. We also evaluated the sensitivity of our results to including a random effects for neighborhoods, represented by Census Tract boundaries. And lastly, we examined the associations between season and birth weight by combining several months into a season variable .After exclusions for missing residential addresses and covariate information and restricting to urban metropolitan areas we examined 2510 births in the CHILD study. Figure 2 and stress are lower in the highest green space quartile compared to the least green quartile, and the WalkScore® measure is higher in the least green areas.Table Table 2 and PM2.5 exposures and neighborhood walkability scores). Mothers with low perceived social support also had larger associations. Models stratified by CHILD cities demonstrated heterogeneous results, with large positive associations between NDVI and birthweight for Toronto and Vancouver and a negative association for Edmonton.Figure Incremental models of hypothesized pathway variables are summarized in Table We evaluated the sensitivity of our main model results to the inclusion of noise estimates (for Vancouver and Toronto), neighborhood random effects, and season. Noise models were available for Vancouver and Toronto. Our main model for these two cities combined showed that a 0.1 unit increase in NDVI is associated with a 41.2 g  increase in term birth weight. This results reflects the larger associations we observed in our Vancouver and Toronto stratified models Fig.  are addeWe investigated the association and potential pathways linking proximity to green space during pregnancy (assessed using NDVI), and term birth weight for 2510 births in four Canadian cities. We observed positive associations between increasing exposure to green space and increased term birth weight in models adjusted for potential individual and neighborhood confounding factors. Overall associations for the four cities were not statistically significant, but stronger statistically significant associations were observed for mothers living in high-density locations and the cities of Vancouver and Toronto. We did not observe substantial reductions in the green space and birth weight association with the addition of hypothesized pathway variables, which was consistent across all cities.Our overall findings of a potential association between residential green space and term birth weight (ranging from 0.4 to 22.1 grams with a 0.1 unit increase in NDVI) generally corresponds to the existing literature. In a separate study in Vancouver Canada, a 0.1 increase in NDVI (within 100 m of mothers homes) was associated with a 20.4 g increase in term birth weight . If we r2 exposure and walkability® scores . We note that in our stratified analyses, we found stronger association for mothers living in apartments/condos compared to those residing in single family detached house, another potential surrogate for density/urbanicity. The types of vegetation and associated biological exposures, the accessibility of green space, proximity to blue space and climate also varies considerably across these four cities, which could affect the nature of the association between green space and term birth weights. Toronto and Vancouver are more moderate climates (− 2 °C average minimum winter temp vs. − 16 °C in Edmonton and Winnipeg); however, our sensitivity analysis including season of birth did not change our findings. The results of our city specific analysis suggest that much more research is needed to understand if green space benefits are restricted to high-density city locations, where green space is limited, and how green space affects may vary across diverse climate conditions.We observed mixed associations across the four Canadian cities included in the CHILD cohort. For Vancouver and Toronto, which are the third and first largest cities in Canada, respectively , we obseUnderstanding how green space may influence birth outcomes is needed and our study is the first to examine a comprehensive number of hypothesized pathways. Opposite to our a priori hypotheses, we found that the pathways examined  did not explain the observed associations between green space and birth weight in these Canadian cities. This suggests that our variables may not be properly measuring the specific hypothesized pathways of interest; that other pathways not included in our models are present; or that the relationship between residential green space and birth outcomes is due to residual or unmeasured confounding factors.2, PM2.5 and O3 did not change the association between NDVI and birth weight. There are mixed findings in the literature as to whether air pollution mediates green space effects and little is known specifically for adverse birth outcomes [2 reduced the magnitude of association between green space and birth weight from 22.3 to 17.1 g [2 and PM2.5, from 12.2 to 16.2 and 14.8 g respectively [In our analysis, controlling for NOoutcomes , 45. Forectively . The com® attenuated the association slightly (though not significantly), while proximity to parks and water had little effect. The correlation between NDVI and Walkscore® was − 0.31. A growing body of research has demonstrated that physical activity during pregnancy can reduce the risk of having a low birth weight baby [Examining the physical activity pathway, we found that Walkscoreght baby –19. UnfoWe observed a negative association between NDVI and mothers who reported depression but not stress. These findings are consistent with a study examining the association between NDVI and stress and depression in twins that found that greater access to green space was associated with less depression but found less evidence for effects on stress . MaternaSocial support has long been considered an important health indicator for women, with research showing that low social support has a significant direct effect on birth weight , 28. In While this analysis contains substantial strengths  and contributes important new information on the associations between green space exposure during pregnancy and term birth weight there are limitations to highlight. First, we used a satellite-derived green space measure (NDVI) around mothers’ residential addresses to assess “exposure” to green space. However, NDVI represents only the presence of green vegetation and does not capture type, quality or use of green space. Nevertheless, we have improved on previous studies by using 30 m NDVI estimates and averages for each 9 month pregnancy period, rather than summer maximum or yearly averages. Second, the variables we had available to measure our proposed pathways are not ideal in all cases  and likely incorporate measurement error . However, this is the first study that has attempted to evaluate such a diverse range of pathways linking green space to birth outcomes and the lack of attenuation in our green space estimates by these pathways cannot be explained by measurement error alone. Third, the mothers in the CHILD cohort are predominantly white, well educated women that have access to universal health care. This limited the variation in several key socio-demographic characteristics that have been shown previously to modify and potentially mediate green space associations with adverse birth outcomes. However, this also reduced the potential that our results are due to residual confounding by SES, a major question in the green space literature. Finally, even though this is a relatively large prospective birth cohort with very detailed data collection, sample size was limited for stratified and pathway analyses.We examined the relationship between green space and term birth weight in a large Canadian birth cohort spanning four cities. We observed positive associations between increasing exposure to green space and increased term birth weight in models adjusted for potential individual and neighborhood confounding factors. Overall associations for the four cities were not statistically significant, but stronger statistically significant associations were observed for mothers living in high-density locations and the cities of Vancouver and Toronto. The hypothesized pathways tested  did not explain these positive associations. Our results highlight the need to characterize the interactions between green space, urban density and climate related factors and further evaluate pathways linking residential green space exposures to improved birth outcomes.


In preterm infants , postnatal growth remains a concern. This study used multicenter longitudinal data from China’s Under 5 Child Nutrition and Health Surveillance System to investigate the postnatal growth in the weight and length of preterm infants. Gender-stratified differences in weight and length were assessed between preterm and term infants. 1221 preterm infants and 1221 matched term infants were included. The rates of growth in weight and length in preterm infants was greater than those in term infants, especially from the first to sixth month. The rates were higher in males compared to females in the first 3 months. The differences of weight and length between preterm and term infants decreased with increasing age, however, these measurements did not reach the level of their term peers until 12 months before adjusting for gestational age. The median values of weight and length were even larger in preterm infants in the first month after adjusting for gestational age. Preterm birth complications are the leading causes of death among children aged under 5 years globally, with an estimated 965000 deaths reported in 2013 , low exest Project established standards for postnatal growth in preterm infants that could be used to assess preterm infants until 64 weeks’ postmenstrual age [In preterm infants, postnatal growth is always a concern. Weight and length are sensitive and convenient indices for evaluating growth in children. Studies have shown that preterm infants are lighter and shorter than same-aged term infants during childhood , 10, whirual age .However, little is known about the early postnatal growth patterns of preterm infants in China. Therefore, we analyzed data from a population-based surveillance system  to compare growth patterns of weight and length in preterm infants within the first year with their term peers.Data from China’s Under 5 Child Nutrition and Health Surveillance System (U5CNHSS) were used in this study. U5CNHSS is a population-based dynamic surveillance system launched by the Chinese government in 2011. The system collects data from a representative sample of 80 districts/counties  across 31 provinces/autonomous regions/municipalities . Then, the number of villages/residential committees in each township/street of the sampled district/county was ranked, and four townships/streets are randomly selected using a systematic sampling method. For each selected township/street, several villages/residential committees were selected until a minimal sample size of 500 under 5 children was reached. This study was approved by the Ethics Committee of West China Second University Hospital, Sichuan University, China.st, 2012 and Sep. 30th, 2013; 2) infants who had at least one record of weight and length measurement during the period from 1 to 12 months of chronological age; and the exclusion criteria is as follows: 1) infants whose gestational age was unknown or less than 27 weeks; 2) infants whose gender was unknown or ambiguity. Then, the study population were further separated into preterm and term infants. All preterm infants who met the inclusion criteria were included. Term infants with gestational age of 40 weeks and 1:1 matched by gender and residence place at the county level (i.e. the same county with the preterm infants) were randomly selected. Since there was no information on the genetic and chromosomal disorders of these subjects, we could not exclude those infants. The flow chart of the study population selection was shown in The inclusion criteria for this analysis is as follows: 1) infants who were born between Oct. 1Unified protocol and forms were used for each surveillance site. Village or community doctors were obligated to register all newborns and under 5 children within their responsible areas and recruit them for health examinations in the township or community health care center. Infants were followed up at 1-, 3-, 6-, 8-, 12-months of chronological age. The health examination included weight and length measurements, a basic physical examination, growth and developmental evaluation, and a questionnaire consisting of questions regarding the demographic information for the household, mother and child; and medical conditions for the mother and child. Gestational age was based on the last menstrual period of the mother and/or first-trimester ultrasonography. The weight and length measurements were obtained by the trained health workers according to the nationwide technical specification of essential public health service . Weight The village or community doctors checked the list of newborns and under 5 children monthly and ensured that each child finished his or her health visit. Health workers in the township or community health care centers double checked the list of children who finished health visits with the village or community doctors and checked the completeness of the forms. Health workers in the county/district-, prefecture-, provincial-, and national-level sampled 2 to 3 surveillance sites semiannually or annually for quality control concerning the workflow, measuring method, instrument adjustment record and data quality at each site.st Preterm Postnatal Growth Standards from 40 to 64 postmenstrual weeks, and used WHO Child Growth Standards from 65 to 88 postmenstrual weeks. The measurements were included in the analysis only if the physical exam time were within 10% days of the specific time points (either before or after adjusting). The size for gestational age was accessed according to China’s neonatal birth weight curve [Preterm infants were defined as those that were born at a gestational age less than 37 weeks. In this study, both chronological age  and corrected age  were used for preterm infants. Postmenstrual age was used for comparison in Figs ht curve . The weiAll statistical analyses were performed by SAS 9.4 software . The statistical significance level for α was set at 0.05.p<0.001). A higher proportion of preterm infants were exclusive breastfed compared to term infants (5.03% vs. 2.72%). No differences were observed in maternal education level and migrant status between the two groups. , and most of the preterm infants (76.09%) were born at greater than 34 gestational weeks. A larger proportion of preterm infants were evaluated as small for gestational age (SGA) compared to term infants (10.07% vs. 7.94%). The average maternal age at delivery was greater in the mothers of preterm infants than the mothers of term infants (29.12±5.06 vs. 27.94±4.40,  groups. .rd to 97th centiles of 2006 WHO Child Growth Standards. Most of the median values for weight and length were greater in both term and preterm infants in our study population during the first 88 postmenstrual weeks when compared to the WHO standards. Preterm infants were even heavier and longer than their term peers at 40 postmenstrual weeks. Furthermore, we could see a rapid growth between 40th and 52th postmenstrual weeks in all groups. (Weight and length for age in males and females for both term and preterm infants were illustrated by median values using postmenstrual age to make equitable comparisons. All measurements were within the 3 groups. .st study. The median values of weight and length in preterm infants increased with increasing age and within the 3rd to 97th centiles for preterm growth standards. Generally speaking, preterm infants in our study were heavier and longer than the standards in both genders. (We further compared the growth pattern of preterm infants with postnatal growth standards for preterm infants in the INTERGROWTH-21genders. .The rates of postnatal growth in weight and length for preterm and term infants during different time periods were listed in In this study, we compared postnatal growth in weight and length during the first year between preterm and term infants. The preterm birth rate identified in this study was 3.53%, which is less than global estimates  but compWe noted that after adjusting for gestational age, preterm infants were consistently heavier and taller than the WHO Child Growth Standards for both males and females, and these measurements for term infants were similar to or larger than the WHO standards. This could be interpreted by the “One Child” policy in China conducted before 2016. Parents and/or other caregivers devote more time and efforts to their only child in the family. They believe the heavier and taller the child is, the healthier the child is. Many studies in China have also reported that Chinese infants are significantly heavier and longer than the age-specific WHO growth standards recommended –19.st Project discovered that the patterns differed between postnatal growth and intrauterine growth [We found that the rates of growth after birth were more rapid in preterm infants, especially from the third to sixth month, and the rates were higher in males than females within the first 3 months. That is, preterm infants showed catch-up growth for some of the deficits in weight and length after birth, and males caught up even faster. This could also explain the phenomenon that preterm infants were even heavier and longer than term infants in the first month after adjusting for gestational age. This finding could be verified by Gong et al.’s study, and they reported even overweight/over-length in preterm infants at a 10th/11th month. The INTERGROWTH-21e growth . When coe growth , the weiHowever, these differences decreased with increasing age and term infants even turn the tide after the sixth month. The weight and length of both males and females in preterm infants did not achieve the median measurements of their term peers. Zhao et al.  found a Studies have reported that catch-up growth could reduce the rate of later stunting and be protective against infection in early life . NeverthWe acknowledged several limitations. First, this study was limited by the study population, infants died within the first month of age could not be included in our study. As is known, preterm infants and infants with low birth weight may be more likely to die during the first month of life than their term peers. Our study may underestimate the rate of preterm birth and overestimate the weight and length of infants, especially preterm infants. Second, since the time point of physical measurements were based on the chronological age, the measurements at the adjusted age for preterm is limited, which made further comparison difficult. Third, due to the study endpoint, this study could not determine whether and when the weight and length of both genders, caught up with their term peers.Preterm infants grew faster than term infants from the first to sixth month after birth. The differences in weight and length between preterm and term infants decreased with increasing age. However, preterm infants did not reach the median values of weight and length for term infants during the first year when using the chronological age.


Globally, preterm birth (PTB) and low infant birth weight (LBW) are leading causes of maternal and child morbidity and mortality. Inadequate water and sanitation access (WASH) are risk factors for PTB and LBW in low-income countries. Physical stress from carrying water and psychosocial stress from addressing sanitation needs in the open may be mechanisms underlying these associations. If so, then living in a community with strong social capital should be able to buffer the adverse effects of WASH on birth outcomes. The objective of this study is to assess the relationships between WASH access and social conditions  on PTB and LBW outcomes among Indian women, and to test whether social conditions modified the association between WASH and birth outcomes.This cohort study examined the effect of pre-birth WASH and social conditions on self-reported PTB status and LBW status for 7,926 women who gave birth between 2004/2005 and 2011/2012 Waves of the India Human Development Survey. PTB and LBW occurred in 14.9% and 15.5% of women, respectively. After adjusting for maternal biological and socioeconomic conditions, PTB was associated with sharing a building/compound latrine (Odds Ratio (OR) = 1.55; 95% Confidence Interval (CI) = 1.01, 2.38) versus private latrine access, but suggested an effect in the opposite direction for sharing a community/public latrine . Open defecation, type of drinking water source, minutes per day spent fetching water, and one-way time to a drinking water source were not associated with PTB. LBW was associated with spending more than two hours per day fetching water compared to less than two hours  and suggested an association with open defecation , but was not associated with other types of sanitation, type of drinking water source, or time to a drinking water source. Harassment of women and girls in the community was associated with both PTB  and LBW . The data also showed a possible association of local crime with LBW . Statistically significant (p<0.05) evidence of effect modification was only found for collective efficacy on the association between type of sanitation access and PTB. In addition, stratified analyses identified differences in effect size for walking time to the primary drinking water source and PTB by crime, sanitation access and PTB by harassment, and total hours per day fetching water and LBW by collective efficacy. Limitations of this observational study include risk of bias, inability to confirm causality, reliance on self-reported outcomes, and limited sub-group sample sizes for testing effect modification.The relationship between adverse birth outcomes and sanitation access, domestic water fetching, crime, and gender-based harassment suggests physical and psychosocial stress are possible mechanisms by which WASH access affects PTB and LBW among Indian women. Interventions that reduce domestic responsibilities related to water and sanitation and change social norms related to gender-based harassment may reduce rates of PTB and LBW in India. Increasing the number of women who successfully carry a healthy, nourished infant to term is critical for achieving the Sustainable Development Goals (SDGs). Spontaneous preterm birth (PTB), caused by onset of labor or rupture of the fetal membranes before 37 completed weeks' gestation, is one of the leading global causes of death in neonates and children under five years of age, as well as maternal complications  . An estiA broad range of risk factors have been linked to PTB and LBW outcomes, including but not limited to maternal reproductive history, race, age, low antenatal care attendance, maternal malnutrition, vaginal and urinary tract infections, history of still birth, and anemia –16. In LThe mechanisms through which WASH affects birth outcomes are potentially multifactorial. Inadequate WASH access can increase the risk of diarrheal and helminthic infections, as well as maternal malnutrition and mortality . Yet, reDetermining whether WASH-related stress affects birth outcomes for women in LMICs is critical for understanding whether the global prevalence of PTB and LBW could be reduced by improving WASH conditions for pregnant women. Studies in LMICs on maternal depression, anxiety, and stress and birth outcomes have focused mostly on intimate partner violence, stress, or abuse –35. OnlyIf stressful WASH conditions increase the risk of adverse birth outcomes, then social capital that reduces a woman’s domestic responsibilities, or exposure to social stressors while fetching water or practicing open defecation, may buffer the effect of inadequate WASH conditions on birth outcomes . Past stIn spite of the overwhelming evidence that stress leads to PTB in high-income populations, and evidence that poor WASH access causes stress for pregnant women, there are no studies explicitly examining the effect of WASH-related stress on birth outcomes in LMIC women. The objective of this study is to (1) investigate the relationship between WASH access and social conditions before birth and PTB and LBW outcomes, and (2) test whether social conditions modify the effect of WASH access on birth outcomes.India has one of the highest burdens of neonatal mortality caused by PTB and LBW . The IndThe outcome variables for this study were extracted from the 2011/2012 survey on the birth status of the most recent child born after 2005 (if multiple children born between survey waves). Variables included (1) a binary variable for whether the participant reported premature labor during the birth of the child, and (2) a binary variable representing maternal perception that the birth weight of the child was small or very small, relative to a normal or above average infant .or public latrine , and (4) open defecation.Information on WASH conditions was extracted from the 2004/2005 surveys to represent conditions prior to (preconception period) or during pregnancy. Four WASH variables were selected based upon their potential to be physically or psychosocially stressful during pregnancy . Type ofInformation on social conditions was extracted from the 2004/2005 surveys to represent conditions prior to (preconception period) or during pregnancy. Two questions measured the general safety of the woman’s village or neighborhood . Gender-Two questions assessed aspects of cognitive social capital within each village or neighborhood. Collective efficacy was measured using a binary variable based on the following question: “In some communities, when there is a water supply problem, people bond together to solve the problem. In other communities, people take care of their own families individually. What is your community like?” Respondents had two response options: bond together to solve problem versus each family solves problems individually. Social cohesion was measured using a binary variable based on the following question: “In this village/neighborhood, do people generally get along with each other or is there some conflict or a lot of conflict?”, contrasting “some conflict” and “a lot of conflict” against “none”. The social capital variables used greater levels of social capital as the reference group.Factors that have previously been shown to be related to birth outcomes, and that may be confounders of the relationship between exposures and outcomes included: geography, household wealth index rank, female education index, religion, mother’s age, age at menarche, parity, history of stillbirth, maternal utilization of antenatal checkups, and maternal use of iron supplements during pregnancy . We inteDescriptive statistics are reported as percent, medians, and counts. Strength of association between WASH and social exposures on occurrence of self-reported PTB and LBW are estimated using outcome-specific generalized linear mixed model  for a binary outcome with logit link function, and a random intercept term to account for variance between states. Effects are reported as odds ratios (OR) and 95% confidence intervals (95% CI). To assess the amount of variance in PTB and LBW outcomes that was accounted for by variation between states, the intra-class correlation coefficients (ICC) of the final models were calculated for each outcome with random effect terms for state.a priori selected confounders (Model 1: WASH Only) to assess individual WASH-adjusted effects and confidence intervals. Second, the four social exposure variables were added to each model  to assess whether social conditions were associated with birth outcomes and whether they altered the associations between WASH exposures and outcomes. Third, interaction terms for social and WASH variables were individually added and assessed for evidence of statistically significant (p<0.05) effect modification. If interaction terms were not significant, they were removed from the fully adjusted Model 2 WASH-Social Model. However, the statistical significance of interactions product terms in nonlinear models can be misleading [The modeling process involved three steps. First, separate PTB and LBW models were constructed with all four WASH variables and sleading . A simplOf 25,789 women who participated in both waves of the IHDS, 7,926 (30.73%) women delivered an infant between 2004/2005 and 2011/2012 and thus were eligible for this study . PTB andThe sample population represented a diverse socio-economic background . Women wMost households (83.38%) had access to a piped tap, borehole, or tube well water source, with only 1.06% reporting use of some form of surface water . Seven pApproximately 11.1% of the variability in PTB prevalence (ICC = 0.111) was accounted for by state-level factors, leaving 88.9% of the variability to be accounted for by other factors. In the model assessing the effects of WASH conditions on PTB, type of water source, time spent walking one way to a drinking water source, spending more than two hours per day fetching water, and type of sanitation access were not significantly associated with premature delivery, after adjusting for potential confounders , Model 1Collective efficacy modified the association between sanitation access and PTB  was accounted for by state-level factors, leaving 94.4% of the variability to be accounted for by other factors. Spending more than two hours per day fetching water was associated with increased odds of delivering a LBW infant, after adjusting for other WASH conditions as well as potential confounders , Model 1No statistically significant effect modification was detected for WASH and social conditions on LBW, although weak interaction (p = 0.092) was detected between spending > 2 hours per day fetching water and collective efficacy . SubgrouPreterm birth and low infant birth weight are among the leading causes of neonatal and early childhood morbidity and mortality in LMICs, like India, and prevalence rates in Africa and Southeast Asia are rising –3. The rThe lack of water and sanitation in the household forces women to navigate challenging, and even personally threatening social and environmental public conditions to fetch water and to find a safe, private place to defecate, bathe, or manage menstruation, leading to psychosocial stress , 22, 43.Open defecation and using a shared latrine within a woman’s building or compound were also associated with higher odds of LBW and PTB, respectively, compared to having a private household toilet. Lack of access to a private toilet forces women to cope with urination, defecation, and menstruation needs in public areas, which increases the amount of time they could experience harassment , 30. TheOur findings demonstrate that poor community-level social conditions are independently associated with both PTB and LBW outcomes, regardless of household WASH conditions, and modify the impact of WASH access on those outcomes. Women who reported that gender-based harassment was common in their community had higher odds of PTB and LBW, and those who reported issues with local crime  were trending towards statistically higher odds of PTB. This expands the evidence in LMICs on the association between maternal stress and birth outcomes beyond intimate partner violence . AlthougTo elucidate the mechanisms through which sources of physical stress and psychosocial stress affect birth outcomes, we examined the interaction between WASH access and a variety of social factors. We found trends suggesting that fetching water outside the household and open defecation were associated with adverse birth outcomes only when community-level crime and gender-based harassment were common, respectively. The effect size for time to a primary drinking water source on PTB grew with increases in one-way walk time compared to women with a household source among women who reported crime, but had a null effect on women who did not report crime in their community. The effect size for harassment on PTB was 33% larger for women sharing a building/compound latrine or practicing open defecation compared to women with private sanitation, suggesting lack of sanitation increases women’s vulnerability to harassment. These relationships were not statistically implicated, due, in part, to small sample sizes for some WASH categories caused by subgroup analysis. Effect sizes for harassment and LBW did not vary across sanitation categories, suggesting that physical stress or open defecation-related risks (other than harassment) contribute to fetal growth restriction. Although coping with uneven terrain, monsoon conditions, and wildlife may further contribute to the set of stressors experienced by women who open defecate, ultimately harassment plays a dominant role in how sanitation affects birth outcomes in this study.We found effect modification by collective efficacy of sanitation for PTB as well as trends that suggested that collective efficacy modified the effect of water fetching on LBW. Specifically, using a within-compound shared latrine was a risk factor for PTB among women who relied on their community to resolve water problems (an indicator of collective efficacy), but not among women who solved problems within their own family. This finding was unexpected, but has two possible explanations. First, it could indicate unmeasured benefits from support by one’s family in managing a shared latrine. Family-level support could reduce the likelihood of depressive symptoms in women, and therefore likelihood of PTB , 58, or Gardnerella vaginalis, Candida spp. or Mycoplasma spp.) that can stimulate myometrium contractions and/or the rupture of chorioamniotic membranes [Additional limitations of our study, beyond power to conduct subgroup analysis, include the use of self-reported birth outcomes, which may be subject to recall or courtesy bias, and limited information on women’s social experiences related to water and sanitation. Despite the data limitations, this is the only data set would allow us to examine environmental and social aspects of WASH access and birth outcomes. Another limitation was the lack of information on potential maternal confounders, such as maternal BMI and reproductive tract infections. Alternative mechanisms associated with unsafe WASH access that could explain our findings include higher risks of malarial, helminthic, or diarrheal infections due to increased contact with public soils and surface waters, or contact with environmental chemical pollutants. Additionally, women with limited WASH access may practice unsafe hygiene behaviors that increase their risk for intrauterine infection by foreign microbes Click here for additional data file.S2 Table(DOCX)Click here for additional data file.S3 TableDid not converge (NC).(DOCX)Click here for additional data file.S4 Table(DOCX)Click here for additional data file.S5 TableDid not converge (NC).(DOCX)Click here for additional data file.