Studies of speech processing investigate the relationship between temporal structure in speech stimuli and neural activity. Despite clear evidence that the brain tracks speech at low frequencies (~ 1 Hz), it is not well understood what linguistic information gives rise to this rhythm. In this study, we harness linguistic theory to draw attention to Intonation Units (IUs), a fundamental prosodic unit of human language, and characterize their temporal structure as captured in the speech envelope, an acoustic representation relevant to the neural processing of speech. IUs are defined by a specific pattern of syllable delivery, together with resets in pitch and articulatory force. Linguistic studies of spontaneous speech indicate that this prosodic segmentation paces new information in language use across diverse languages. Therefore, IUs provide a universal structural cue for the cognitive dynamics of speech production and comprehension. We study the relation between IUs and periodicities in the speech envelope, applying methods from investigations of neural synchronization. Our sample includes recordings from every-day speech contexts of over 100 speakers and six languages. We find that sequences of IUs form a consistent low-frequency rhythm and constitute a significant periodic cue within the speech envelope. Our findings allow to predict that IUs are utilized by the neural system when tracking speech. The methods we introduce here facilitate testing this prediction in the future . Such research has revealed that neural activity tracks amplitude modulations present in speech. It is generally agreed that a dominant element in the neural tracking of speech is a 5 Hz rhythmic component, which corresponds to the rate of syllables in speech8. The speech stimulus is also tracked at lower frequencies , but the functional role of these fluctuations is not fully understood. They are assumed to relate to the “musical” elements of speech which are above the word level—called prosody. However, prosody in the neuroscience literature is rarely investigated for its structure and function in cognition.Speech processing is commonly investigated by the measurement of brain activity as it relates to the acoustic speech stimulus10. Importantly, in addition to providing a systematic segmentation to ongoing naturalistic speech, IUs capture the pacing of information, parceling a maximum of one new idea per IU. Thus, IUs provide a valuable construct for quantifying how ongoing speech serves cognition in individual and interpersonal contexts. The first goal of our study is to introduce this understanding of prosodic segmentation from linguistic theory to the neuroscientific community. The second goal is to put forth a temporal characterization of IUs, and hence offer a precise, theoretically-motivated interpretation of the low-frequency auditory tracking and its relevance to cognition.In contrast, the role of prosody in speech and cognition are extensively studied within the field of linguistics. Such research identifies prosodic segmentation cues that are common to all languages, and that characterize what is termed Intonation Units  Phrases (e.g.19), intonation-groups (e.g.14), tone-groups20, and intonation units (e.g.12). We adopt here the term Intonation Unit to reflect that our main interest in these chunks lies in their relevance for the processing of information in naturalistic, spontaneous discourse, an aspect foregrounded by Chafe and colleagues. To this important function of IUs we turn next.When speakers talk, they produce their utterances in chunks with a specific prosodic profile, a profile which is attested in presumably all human languages regardless of their phonological and morphosyntactic structure. The prosodic profile is characterized by the intersection of rhythmic, melodic, and articulatory properties23. For example, when speakers develop a narrative, they do so gradually, introducing the setting, participants and the course of events in sequences of IUs, where no more than one new piece of information relative to the preceding discourse is added per IU  actions25 (but cf.26). For example, when speakers coordinate a transition during a turn-taking sequence, they rely on prosodic segmentation : points of semantic/syntactic phrase closure are not a sufficient cue for predicting when a transition will take place, and IU design is found to serve a crucial role in timing the next turn-taking transition29.Across languages, these prosodically-defined units are also functionally comparable in that they pace the flow of information in the course of speechr IU Box . This haHere we use recordings of spontaneous speech in natural settings to characterize the temporal structure of sequences of IUs in six languages. The sample includes well-studied languages from the Eurasian macro-area, as well as much lesser-known and -studied languages, spoken in the Indonesian-governed part of Papua by smaller speech communities. Importantly, our results generalize across this linguistic diversity, despite the substantial differences in socio-cultural settings and all aspects of grammar, including other prosodic characteristics. In contrast to previous research, we estimate the temporal structure of IUs using direct time measurements rather than word or syllable counts Box . In addiBox 1: Information is temporally structured in social interaction30. This is especially evident in task-oriented interaction, for example, in direction-giving sequences during navigation, or instruction sequences more broadly, where the many deictic words  can only be interpreted correctly when accompanied by a timely gesture. Following is such a fragment from a judo-instruction class11. The prosodic-based segmentation into IUs is represented by a break in line, such that each line corresponds to on IU. To facilitate reading, transcription conventions were simplified . Speaker overlap is marked by square brackets (  ), minimally audible to medium pauses (up to 0.6 s) are marked by sequences of dots ( … ) and punctuation marks represent different functional classes of pitch movements, indicating roughly the degree of continuity between one unit and the next .Time is crucial for organizing information in interaction, not only via prosodic cues but also through body conduct, such as gaze-direction, head and hand gestures, leg movements and body torquesBox 2: What is a word?31). We demonstrate why this is so for cross-linguistic comparison with the following example in Seneca, a member of the Northern Iroquoian branch of the Iroquoian language family spoken in Northeast America32.The notion of a word has been argued to be untenable for both language-specific and cross-linguistic analyses , obtained through linguistic analysis and comparative evidence from related languages. Due to extensive sound changes over the years, Seneca shows a high degree of fusion between meaning components, that is, the boundaries between them are obscured and not necessarily available to speakers. Note also that these meaning components cannot normally appear as independent words, that is, without the neighboring meaning components. The third line includes a gloss per meaning component, differentiating between those with grammatical meaning  and content items. The fourth line includes the corresponding English translation.As evident from this example, a noteworthy distinction between Seneca and some better-known languages of the world such as English is that Seneca regularly packages an event, its participants and other meaning components within a single morphosyntactic word. Consequently, for one and the same message, Seneca IUs would contain fewer words compared to English IUs.34.Many other linguistic constructs vary greatly from language to language. In fact, it seems that linguistic diversity is the rule rather than the exception, and that care should be taken to avoid a priori taxonomies that would fail when considering the next language9 and colleagues . This segmentation process involves close listening to the rhythmic and melodic cues presented in the introduction, as well as performing manually-adjusted acoustic analyses, the latter particularly for the extraction of pitch contours (f0) which are used to support perceived resets in pitch. Three of the corpora were segmented by specialist teams working on their native language: the Santa Barbara Corpus of Spoken American English11, the Haifa Corpus of Spoken Hebrew35, and the Russian Multichannel Discourse corpus36. The other three corpora were segmented by a single research team whose members had varying degrees of familiarity with the languages, as part of a project studying the human ability to identify IUs in unfamiliar languages: the DoBeS Summits-PAGE Collection of Papuan Malay37, the DoBeS Wooi Documentation38, and the DoBes Yali Documentation39. The segmentation of each recording is typically performed by multiple team members and verified by a senior member experienced in auditory analyses in the language. Such was the process in the corpora above, ensuring that ambiguous cases were resolved as consistently as possible for human annotators and that the transcriptions validly represent the language at hand. Further information regarding the sample is found in Table We studied the temporal structure of IUs using six corpora which included spontaneously produced conversations and unscripted narratives. The corpora were all transcribed and segmented into IUs according to the unified criteria devised by Chafe40. In this analysis, the rhythmicity of IU sequences is measured through the phase consistency of IU onsets with respect to the periodic components of the speech envelope . In another scenario, if the speech envelope captures slow rhythmicity in language other than that arising from IUs, different IUs would occur in different phases of the lower frequency components, translating again to low phase consistency. In contrast to these scenarios, finding phase consistency at a degree higher than expected under the null hypothesis would indicate both that the speech envelope captures the rhythmic characteristics of IUs and would characterize the period of this rhythmicity.8 . Of note, the highest phase consistency is measured at 1 Hz in all languages except Hebrew, in which the peak is at the neighboring frequency bin, 1.5 Hz.We studied the temporal structure of IU sequences through their alignment with the periodic components of the speech envelope, using a phase-consistency analysis. We hypothesized that one of the characteristics of IUs – the fast-slow dynamic of syllables—would give rise to slow periodic modulations in the speech envelope. Seeing that IUs analyzed here are informed by a cognitively-oriented linguistic theory and have a wide cross-linguistic validity we hypothesize that comparable periodicity will be found in different languages. Figure To complement the results of the phase-consistency analysis, we estimated the median duration of IUs Fig. , insets.We sought to confirm that this effect was not a result of an amplitude transient at the beginning of IU sequences, or the product of pauses in the recording, that affect the stationarity of the signal and may bias its spectral characterization. To this end, we repeated the analysis, submitting only IUs that followed an inter-IU interval below 1 s, that is, between 65 and 89% of the data, depending on the language Table .44. The direct time measurements we used obviate the pitfalls of length measurements in word count or syllable count, (e.g.23). The temporal structure of IUs cannot be inferred from reported word counts, because what constitutes a word varies greatly across languages (Box 45), but it does not capture information about the temporal structure of IU sequences.Our results are consistent with preliminary characterizations of the temporal structure of IUsunt, e.g.3. The te1. Studies identify also slower oscillations, in the delta range (~ 1 Hz), and have attributed them to segmentation at the level of phrases, both prosodic and formal, such as semantic/syntactic phrases51. Previous studies have consistently demonstrated a decrease in high-frequency neural activity at points of semantic/syntactic completion52 or natural pauses between phrases53. This pattern of activity yields a slow modulation aligned to phrase structure. We harness linguistic theory to offer a conceptual framework for such slow modulations. We quantify the phase consistency between acoustical slow modulations and IU onsets, and demonstrate for the first time that prosodic units with established functions in cognition give rise to a low-frequency rhythm in the auditory signal available to listeners.Neuroscientific studies suggest that neural oscillations participate in segmenting the auditory signal and encoding linguistic units during speech perception. Many studies focus on the role of oscillations in the theta range (~ 5 Hz) and in the gamma range (> 40 Hz). The levels of segmentation attributed to these ranges are the syllable level and the fine-grain encoding of phonetic detail, respectively54 provided a linguistically-informed interpretation that these low frequency modulations are associated with stress elements of speech. There are two important differences between the present study and Tilsen and Arvaniti54. The current work directly interrogates the temporal structure of a linguistically labeled construct—the IU. Furthermore, prosodic prominence structure and IUs contrast on an important issue. While prominence structure differs between languages55, IUs are conceptually universal10. In our characterization of the temporal structure of the IUs we contribute empirical evidence to the conceptual notion of universality. The temporal structure found in the speech envelope around labeled IUs is common to languages of dramatically different prosodic systems . Finally, unlike IUs, prominence is also marked by different phonetic cues in different languages, so any acoustic analysis focusing on the acoustic correlates of prominence is bound to find cross-linguistic differences.A previous study identified low-frequency modulations in the speech acoustics. Analyzing a representation of speech acoustics similar to the speech envelope used here, Tilsen and Arvaniti56. From the perspective of studying the temporal structure of spontaneous speech, we suggest that the distinction maintained between semantic/syntactic and prosodic phrasing might be superficial. That is because the semantic/syntactic building blocks always appear within prosodic phrases in natural language use60. Studies investigating semantic/syntactic building blocks often compare the temporal dynamics of intact grammatical structure to word lists or grammatical structure in an unfamiliar language (e.g.52). We argue that such studies need to incorporate the possibility that ongoing processing dynamics might reflect perceptual chunking, owing to the ubiquity of prosodic segmentation cues in natural language experience. This possibility is further supported by the fact that theoretically-defined semantic/syntactic boundaries are known to enhance the perception of prosodic boundaries, even when those are artificially removed from the speech segment. In a study that investigated the role of syntactic structure in guiding the perception of prosody in naturalistic speech61, syntactic structure was found to make an independent contribution to the perception of prosodic grouping. Another study equated prosodic boundary strength experimentally , and found the same result: semantic/syntactic completion contributed to boundary perception62. Even studies that use visual serial word presentation paradigms rather than auditory stimuli are not immune to an interpretation of prosodically-guided perceptual chunking, which is known to affect silent reading63 (for a review see64).Previous research in cognitive neuroscience has proposed to dissociate delta activity that represents acoustically-driven segmentation following prosodic phrases from delta activity that represents knowledge-based segmentation of semantic/syntactic phrases58, our results point to another putative role for slow rhythmic brain activity. We find that orthogonal to different grammatical systems, speakers and speech modes, speakers express their developing ideas at a rate of approximately 1 Hz. Previous studies have shown that in the brains of listeners, a wide network interacts with low-frequency auditory-tracking activity, suggesting an interface of prediction and attention-related processes, memory and the language system67. We expect that via such low-frequency interactions, this same network constraints spontaneous speech production, orchestrating the management and communication of conceptual foci9.Independently of whether delta activity in the brain of the listener represents acoustic landmarks, abstract knowledge, or the prosodically-mediated embodiment of abstract knowledgeFinally, our findings render plausible several hypotheses within the field of linguistics. At a basic level, the consistent duration of IUs may provide a temporal upper bound to the construal of other linguistic units .Supplementary Information


Non-obstetric surgery conducted during pregnancy may increase the risk of adverse birth outcomes like small for gestational age, preterm birth, and miscarriage. Mechanisms are unclear but possibly longer lasting. We examined whether appendectomy, cholecystectomy and diagnostic laparoscopy conducted before pregnancy affect these outcomes.This nationwide Danish prevalence study included all pregnancies during 1996–2015 that had an appendectomy, cholecystectomy or diagnostic laparoscopy registered before last menstrual period in the years 1992–2015. We excluded pregnancies with surgery and categorized pre-pregnancy surgery according to timing . Outcomes were small for gestational age, late preterm birth (32–37 weeks), early preterm birth (22–31 weeks) and miscarriage (7–21 weeks). We computed absolute risks and used logistic regression comparing pregnancies with surgery 0–11 or 12–23 to 24+ months before last menstrual period, computing odds ratios for each outcome, adjusting for maternal age and smoking.We identified 15,939 pregnancies with appendectomy, 12,869 pregnancies with cholecystectomy and 19,330 pregnancies with diagnostic laparoscopy. The absolute risk of small for gestational age was 2.2% for patients with appendectomy 0–11 months before last menstrual period, 3.2% 12–23 months before compared with 2.2% when appendectomy was conducted more than 24 months before  and 1.37. For early preterm birth, the absolute risks were 0.7, 0.5 and 0.8%, for late preterm birth 4.8, 4.4 and 4.7% and for miscarriage 5.7, 6.2 and 5.4%.We observed similar results for cholecystectomy. For diagnostic laparoscopy 0–11 months before pregnancy we found increased risks of small for gestational age  and late preterm birth .We found no increased risk of adverse birth outcomes among pregnancies with appendectomy or cholecystectomy conducted within 2 years before pregnancy compared to more than 2 years before pregnancy. The increased risks 0–11 months after diagnostic laparoscopy are likely explained by confounding by underlying indication. It appears safe to become pregnant any time following appendectomy and cholecystectomy, but, probably depending on indication, attention should be payed 0–11 months after diagnostic laparoscopy. Appendectomy, cholecystectomy, diagnostic laparoscopy and other non-obstetric surgery conducted during pregnancy may affect the risk of adverse obstetrical outcomes, including increased risk of preterm birth –4, smallThis national prevalence study was based on a population of 5.7 million inhabitants in Denmark , with anThrough DMBR and DNPR, we identified all Danish female citizens aged 15–54 years who delivered during the period 1995–2016. We restricted to singleton births, because multiple births are associated with both lower fetal weight  and lowe> 22 weeks are included [We extracted information on birth weight and gestational age from the DMBR, which was established in 1973. It contains information on all home and hospital deliveries in Denmark. Livebirths regardless of gestational age and stillbirths included . Data inincluded . We calcWe then restricted the study population to women with appendectomy, cholecystectomy or diagnostic laparoscopy  and risk difference (RD) of SGA, early preterm birth, late preterm birth and miscarriage for all groups. We used logistic regression analysis to calculate odds ratios (ORs) of the association of timing of surgery , with surgery > 24 months before LMP as reference, and risk of SGA, late preterm birth, early preterm birth, and miscarriage after week 7, respectively. In the regression analysis, we adjusted for maternal smoking and maternal age using multiple imputation to account for missing information on smoking status. We tabulated diagnosis codes related to diagnostic laparoscopy and performed a regression analysis for the two main diagnosis groups. We performed an analysis with only complete cases of smoking status and an analysis with women with appendectomies performed more than 5 years before pregnancy as reference group as sensitivity analyses. For miscarriages, we adjusted for maternal age. We stratified the analysis by year of surgery  for appendectomies, cholecystectomies and diagnostic laparoscopies conducted anytime between 0 and 23 months compared with the same surgery We used the statistical software package STATA  for data analysis.Among 1,173,500 pregnancies without major surgery during pregnancy from Denmark in 1996–2015, we identified 15,939 with appendectomy before LMP, 12869 with cholecystectomy before LMP and 19,330 with diagnostic laparoscopy before LMP  and 1.4 , respectively. For late preterm birth the risks were 4.8, 4.4 and 4.7%, respectively and for early preterm birth 0.7, 0.5, and 0.8%, respectively. The adjusted ORs for late preterm and early preterm birth varied between 0.6 and 1.0. The risks for miscarriages after GA week 7 were 5.7, 6.2 and 5.4% with adjusted ORs of 1.1 and 1.3, respectively  and early preterm birth in pregnancies 12–23 months after cholecystectomy on 1.2 ) Table  and for In this population-based study with more than 46,000 pregnancies with surgery before LMP, we found no major elevated risks of SGA, early preterm birth, late preterm birth and miscarriage after GA week 7 following appendectomy and cholecystectomy. For diagnostic laparoscopy, an association with SGA, early preterm birth and late preterm birth, could not be excluded. However, the precision of our estimates do not allow us to draw any firm conclusions.Disentangling the effect of surgery from the effect of the underlying condition is difficult and causal mechanisms are uncertain. However, if the laparoscopic procedure itself is associated with elevated risks, we would expect increased risks following appendectomy and cholecystectomy as well. The possibly increased risks following diagnostic laparoscopy could therefore likely be explained by confounding by underlying indications. We did not analyze open and laparoscopic procedures separately due to small numbers, but Ibiebele et al.  showed tTo our knowledge, no previous studies have addressed these questions, and our findings thus adds to the existing literature. A cohort study showed an association between previous bariatric surgery and adverse obstetric outcomes , but indIt is a strength of our study that the risk of selection bias is low as the included registries are virtually complete , 13. HowIt is a limitation to our study that we lacked information on maternal complications during or after surgery, since such complications could affect the risk of adverse birth outcomes in following pregnancies. However, as we examined the risk of adverse birth outcomes after the last surgery before pregnancy, there would be no surgical complications to these. The fact, that diagnostic laparoscopy is conducted on a variety of indications which may to varying degree be present during a following pregnancy prevents a firm conclusion regarding the actual impact of surgery itself on adverse birth outcomes. Additional to varying indications for surgery, different types of anesthesia might also influence birth outcomes in subsequent pregnancies .More hypotheses can explain why the post-surgical changes in maternal microbiome and pro-inflammatory mediators known in relation to surgery do not seem to increase the risk of adverse obstetrical outcomes , 26 whenBased on our findings, we conclude, that it appears safe to conceive any time after appendectomy and cholecystectomy regarding obstetric outcomes. Probably depending on indication, attention should be payed 0–11 months after diagnostic laparoscopy.Additional file 1. Surgical codes used to identify minor procedures and procedures related to birth and fetal diagnostics. These procedures were not included in the definition of surgery during pregnancy.Additional file 2. Surgical codes used to identify, appendectomies, cholecystectomies, and diagnostic laparoscopy, respectively.Additional file 3. Demographic information on women with cholecystectomy before pregnancyAdditional file 4. Demographic information on women with diagnostic laparoscopy before pregnancyAdditional file 5. Development in odds ratio (OR) with 95% confidence interval (CI) by year-group of surgery. Legend: Adjusted odds ratio (aOR) of small for gestational age (SGA), early preterm birth, late preterm birth and miscarriage among women who underwent cholecystectomy 0–23 months before pregnancy, compared with women who underwent cholecystectomy at least 24 months before pregnancy from 1996 to 2015Additional file 6. Development in odds ratio (OR) with 95% confidence interval (CI) by year-group of surgery. Legend: Adjusted odds ratio (aOR) of small for gestational age (SGA), early preterm birth, late preterm birth and miscarriage among women who underwent diagnostic laparoscopy 0–23 months before pregnancy, compared with women who underwent diagnostic laparoscopy at least 24 months before pregnancy from 1996 to 2015Additional file 7. Main diagnosis groups in women with diagnostic laparoscopy from 1996 to 2015. Legend: The diagram shows the prevalence (%) of diagnosis groups among diagnostic laparoscopies from 1996 onwards in total, diagnostic laparoscopies conducted 0–11 months before pregnancy, 12–23 months before pregnancy and more than 24 months before pregnancy.Additional file 8. Odds ratios of adverse birth outcomes after diagnostic laparoscopy before pregnancy when diagnosis was urogenital disorder or unspecific symptoms. Legend: Prevalence, crude and adjusted odds ratios (cOR/aOR) of small for gestational age (SGA), early preterm birth, late preterm birth and miscarriage in pregnancies with diagnostic laparoscopy before pregnancy when diagnosis was urogenital disorder or unspecific symptoms


The magnitude of adverse birth outcome among diabetic pregnant women is high in low-and-middle income countries, like Ethiopia. Precise epidemiological evidence is necessary to plan, evaluate and improve effective preventive measures. This systematic review and meta-analysis is the first to estimate the pooled prevalence of adverse birth outcome and associated factors among diabetic pregnant women in Ethiopia.2 statistic was used to check heterogeneity. Egger’s test and funnel plot were used to measure publication bias. Weighted inverse variance random effects model was also performed.PubMed, Cochrane Library, Google Scholar, SCOPUS, Web of Science and PsycINFO, and article found in University online repository were accessed. Observational studies such as cross-sectional, case-control and prospective cohort reported using English language was involved. ISeven studies with 1,225 study participants were retrieved to estimate the pooled prevalence of adverse birth outcome and associated factors. The pooled prevalence of adverse birth outcome among diabetic pregnant women was 5.3% . Fasting blood glucose level above 100 mg/dl , two hour post prandial glucose level above 120 mg/dl , gestational age <37 completed week , no ANC follow-up , history of previous adverse outcomes , maternal age < 30 years , and illiteracy  were associated factors of adverse birth outcome.The pooled prevalence of adverse birth outcomes among diabetic pregnant women in Ethiopia was high. Child born from mothers who were illiterate, maternal age < 30 years, gestational age < 37 completed weeks, history of previous adverse birth outcomes and no ANC follow-up increased the risk of adverse birth outcome.CRD42020167734).It is registered in PROSPERO data base: (PROSPERO 2020:  Diabetes Mellitus (DM) is a group of metabolic disorders characterized by a high blood sugar level over a prolonged period of time and caused by either from deficiency in insulin secretion, decreased insulin action or both . Along wDM in pregnancy can be gestational DM; affects 2–3% of pregnancy  and pre-Despite preterm birth has been occurred in general population; the risk is higher among diabetic pregnant women. According to 2016 World Health Organization (WHO) report, the risk of preterm birth from diabetics mother were increased by 5% in LMICs . SimilarEvidence advocated that inadequate antenatal, medical, and preconception care are factors affecting adverse birth outcomes among diabetic women , 25, 26.Even though, the government of Ethiopia set different plan and strategies to combat this problem; it is still the major public health issue . StudiesThis systematic review and meta-analysis was designated to estimate the pooled prevalence of adverse birth outcomes and associated factors among diabetic pregnant women in Ethiopia. The result is reported based on standard Preferred Reporting Items for Systematic review and Meta-analysis (PRISMA) checklist  S1 Chec. The revInternational data bases, which are PubMed, Cochrane Library, Google Scholar, SCOPUS, Web of Science and PsycINFO, and article found in Addis Ababa and Haramaya University online repository, were searched. Reference lists and citations of included papers were checked to identify any other potentially relevant papers. Compressive search strategy from March 29/2020 to May 26/ 2020 has been employed using Population, Intervention, comparison and Outcomes (PICO) formulating question and search terms . “AND” and “OR” Boolean operators were used to combined search terms.Five articles published from year 2013–2019 and two unpublished articles in Addis Ababa and Haramaya University online repository reported in English language was selected for analysis. Observational studies such as cross-sectional, case-control and prospective cohort study reporting the prevalence of adverse birth outcomes or and a minimum of one contributing factors for adverse birth outcomes conducted in Ethiopia were included. Studies which used WHO diabetes mellitus diagnosis approach were included. Ethiopia has been used WHO diagnosis approach; based on this; diabetes in pregnancy should be diagnosed if one or more of the following conditions were met: (1) fasting plasma glucose greater or equal to 7 mmol/l (126mg/dl); 2-hour plasma glucose greater or equal to 11.1mmol/l (200mg/dl) following a 75 g oral glucose load; (3) random plasma glucose greater or equal to 11.1 mmol/l (200mg/dl) in the presence of diabetes symptoms. However, articles without full-text or abstract, with JBI critical appraisal score less than 50% and not reporting the outcomes of the interest were excluded.All retrieved studies were exported to EndNote version 9  reference manager and duplicated studies were carefully removed. Two investigator (BM and AS) independently screened the titles and abstracts which were followed by a full text review to determine eligibility of each study. Any difference was resolved by third author (W.A). Two authors (D.M. and B.M.) evaluated independently the eligibility of all retrieved studies by using the Joanna Briggs Institute (JBI) quality appraisal checklist adapted for studies reporting prevalence data, cross-sectional, prospective cohort and case-control studies . The folAfter collecting the required finding form the entire databases, all important data were extracted by authors  using standardized JBI data extraction form and cross cheeked to ensure consistency. Three independent authors  extract data on author/s name, year of publication/study, study area/region, study design, sample size, prevalence of adverse fetal outcome with 95% CI and associated factors were collected. Any dissimilarity and inconsistencies were resolved among the authors by discussion and repeating the procedure. The reviewer contacted the corresponding author(s) for further information whenever pertinent data were missed from the included studies.Adverse birth outcomes: The presence of at least one of the adverse outcome .2 25, 50, and 75% represented low, moderate and high heterogeneity respectively. A p-value of less than 0.05 was used to declare significant heterogeneity   observed.Seven studies with 1,225 participants were retrieved. The overall pooled prevalence of adverse birth outcome among diabetic women in Ethiopia was 5.3%  . No heteVisual inspection of the funnel plot was used to assess asymmetry distributions of the adverse birth outcome . Egger’sTrim and fill analysis was done, three studies were added and the total number of the studies become 10. The pooled prevalence of adverse birth outcomes is 1.2 at p-value 0.052 .2 = 0.0%, p = 0.656).Given that the result of this meta-analysis revealed no a statistically significant heterogeneity among studies to show the overall pooled prevalence of adverse birth outcome ], and average 2 hour post prandial glucose level above 120mg/dl [AOR = 8.77 ] increase the odds of adverse birth outcome among diabetic pregnant women as compared with that of non-diabetic women.Different studies done in different hospital of Addis Ababa indicated that the odds of having adverse birth outcome was 9.76, 10.78, and 3.47 times higher among diabetic pregnant women with gestational age less than 37 completed week [AOR = 9.76 ], no ANC follow up [AOR = 10.78 ], and previous adverse outcome [AOR = 3.47 ] respectively.Two different studies in Tikur Anbessa Specialized Hospital and one study in selected governmental hospital, Addis Ababa indicated that the odds of having adverse birth outcomes among diabetics women age less than 30 years old was 3.47 [AOR = 3.47 ] times higher as compared with its counterpart. Similarly, a study in Hiwot Fana Specialized University Hospital and Dilchora Hospital showed that the odds of having adverse birth outcome among diabetic illiterate women was 2.89 . This is in line with the study done in Kathmandu Medical College Teaching Hospital 8.89% , KulasheBut, the finding in Ethiopia is lower than the study done in Trichy SRM Medical College Hospital (70%) , BhumiboHowever, the finding form this review is higher than retrospective cohort study conducted in Qatar 1.05% . The pos1C in the fetus which result in congenital anomaly and spontaneous abortion  was 3.47 times higher as compared with its counterpart. It is due to the fact that maternal age 25–34 years old has high body mass index (obese)  and lipiIt is better to give great stress for mother with previous history of adverse birth outcome. It is also recommended that providing and strengthening regular and timely focused antenatal care service and early detection and timely maternal glycemic control shall be given a particular emphasis. Moreover, it is better to provide health education for the community about adverse birth outcomes.This study is the first systematic review and meta-analysis that estimate the national prevalence of adverse birth outcomes and contributing factors among diabetic women. Limited numbers of primary articles are used proportionally in each regions of the country. All the studies are institutional based which affects the representativeness to the general community. In additions, there were no sufficient studies about the possible risk factor for adverse birth outcome.According to this systematic review and meta-analysis, the pooled prevalence of adverse birth outcome among diabetic women in Ethiopia was 5.3%. Unable to read and write, maternal age less than 30 years old, gestational age less than 37 completed weeks, previous adverse birth outcomes and no ANC follow up was significantly associated with adverse birth outcomes. So, early screening of diabetes during pregnancy and follow up is important to alleviate the burden of maternal and neonatal adverse birth outcomes. In addition, concern should be given in improving antenatal follow up.S1 Checklist(DOC)Click here for additional data file. 3 Oct 2020PONE-D-20-26756Adverse Birth Outcomes and Associated Factors among Diabetic Pregnant Women in Ethiopia; Systematic review and Meta-analysisPLOS ONEDear Dr. Belay,Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. 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Is the manuscript technically sound, and do the data support the conclusions?The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. Reviewer #1: Partly**********2. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes**********3. Have the authors made all data underlying the findings in their manuscript fully available?PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.The Reviewer #1: Yes**********4. Is the manuscript presented in an intelligible fashion and written in standard English?PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.Reviewer #1: No**********5. Review Comments to the AuthorPlease use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. Reviewer #1: I would like to congratulate the authors to address such a good topic to discussion. It is so important to bring to light the information about diabetes, which is an underestimated and poor screened disease during pregnancy. It is a condition which is relatively cheap to be detected and when in the majority of the cases have a good control with conservative approach but the implications of not address it is importance could affect negatively mother and children.All my comments are in order to improve the quality of the paper for the reader.TittleThe title is appropriate and brings curiosity for the reader to continue reading.AbstractThe abstract is appropriate, however, if you agree to change the points of the text, this must also be readjusted in the abstract.Introduction session#1 The first paragraph of the introduction is a little bit complicated to understand, I suggest a major review of the English and rewrite it for better read.#2 In the second paragraph: what do you mean with “pre-gestational DM”, it is a little confuse with the previous information of the first paragraph, please rephrase it to a single paragraph for further clarification. In addition I suggest add a reference to “Gestational DM affect 2-3% of pregnancy and pre-gestational DM affect 0.2-0.3% of pregnancy is the most common metabolic abnormalities of pregnancy which result in different adverse birth outcomes both for the mothers and neonates.”#3 I also recommend to replace the term diabetic mother to a women with hyperglycaemic pregnancy.#4 During all introduction section you referred to DM 1 and 2 and GDM, but your target is the hyperglycaemic pregnancies, so I think that is interesting bring some data separately in the first paragraph but in the others make sense to refer to this pregnancy condition as hyperglycemic disturbs (or any other similar expression).# 5 In third paragraph the authors bring some interesting informations but I recommend rephrase it and use story telling technique to clarify and connect all the informations and paragraphs. In addition I suggest to delete the phrase “which is important for policy maker to set preventive strategies.” in the end of the introduction and add it to discussion section.Methods session# 6 Indicate if a review protocol exists, if and where it can be accessed , and, if available, provide registration information including registration number.# 7 It is nuclear about the publication years of the articles selected, language, publication status#8 I would like to recommend you to change the expression “poor quality” for the reason, I mean, which was the problem to not include it? Study design? Sample size? Not clear outcomes?# 9 In phrase “the prospective follow up study reporting the prevalence of adverse birth outcomes or and a minimum of one contributing factors for adverse birth outcomes conducted in Ethiopia were included”. Did you establish a minimum and maximal follow up period? Let this information clear.# 10 Please replace still births to stillbirths# 11 Please replace soft wear to software in the phrase “The extracted data were transferred to STATA version 14 statistical soft wear for meta-analysis”Results session#12 In the first paragraph “Three hundred seventy seven articles were retrieved using a search strategy from PubMed, Cochrane Library, Google Scholar, SCOPUS, Web of Science and PsycINFO”, you didn’t mentioned the Addis Ababa and Haramaya University online repository.# 13 I highly recommend to add the references into the tables to allow the reader find the articles easier.#14 Table 4 was included Maternal age <35 years but in the text in socio-demographic factors session “Addis Ababa indicated that the odds of having adverse birth outcomes among diabetics women age less than 30 years old was 3.47” please clarify this point for us.#15 Your results bring more than the purposed by the aim of your paper. “Therefore, this systematic review and meta-analysis is the first aimed to estimate the pooled prevalence ofadverse birth outcomes and associated factors among diabetic pregnant women in Ethiopia which is important for policy maker to set preventive strategies.” You actually brings the prevalence, pregnancy related risk factors and the adverse birth outcomes and during your data presentation in table 1, I expected that the pregnancy related risk factors should be present on it.#16 Another concern is about the measure units in the table, please review it. I suggest to fix two decimal cases as standard to the table values.Discussion Session# 17 In order to improve the discussion I highly recommend the use of storytelling techniques to help you to delineate the findings and discuss it with the already included data. In the first phrase is interesting to add the mainly findings in an easy and quickly summarization to the reader follow the discussion topics of each findings and its possible explanation.#18 It is of paramount importance to perform a major English revisionConclusion Session#19 The conclusion should address the aim.AIM: “To estimate the pooled prevalence of adverse birth outcomes and associated factors among diabetic pregnant women in Ethiopia which is important for policy maker to set preventive strategies.”Conclusion: “According to this systematic review and meta-analysis, the pooled prevalence of adverse birth outcome among diabetic women in Ethiopia was high. Unable to read and write, maternal age less than 30 years old, gestational age less than 37 completed weeks, previous adverse birth outcomes and no ANC follow up was significantly associated with adverse birth outcomes.”I would like to rephrase the conclusion to further clarification. The phrase “Ethiopia was high” comparing to????. I suggest to replace by the %.In addition, again I will insist that your data brings not only the prevalence of adverse birth outcomes, pregnancy related risk factors, but the adverse birth outcomes, and it should be addressed in the conclusion and in the aim.Thank´s.**********what does this mean?). If published, this will include your full peer review and any attached files.6. PLOS authors have the option to publish the peer review history of their article  digital diagnostic tool,  14 Oct 2020Point by point Author’s response to reviewer question and comment Editorial comment and suggestion: https://journals.plos.org/plosone/s/file? id=wjVg/PLOSOne_ formatting_ sample_main_body.pdf and https://journals.plos.org/plosone/s/file?i d=ba62/PLOSOne_ formatting_sample_title_authors_affiliations.pdf1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at 2. We suggest you thoroughly copyedit your manuscript for language usage, spelling, and grammar. If you do not know anyone who can help you do this, you may wish to consider employing a professional scientific editing service. http://learn.aje.com/plos/) for a 15% discount off AJE services. To take advantage of our partnership with Editage, visit the Editage website (www.editage.com) and enter referral code PLOSEDIT for a 15% discount off Editage services. If the PLOS editorial team finds any language issues in text that either AJE or Editage has edited, the service provider will re-edit the text for free.Whilst you may use any professional scientific editing service of your choice, PLOS has partnered with both American Journal Experts (AJE) and Editage to provide discounted services to PLOS authors. Both organizations have experience helping authors meet PLOS guidelines and can provide language editing, translation, manuscript formatting, and figure formatting to ensure your manuscript meets our submission guidelines. To take advantage of our partnership with AJE, visit the AJE website .Author’s response: We add sentence which referred about hyperglycemic pregnancies in introduction section on page 1, line 5 - 7.Question and comments #6: In third paragraph the authors bring some interesting information but I recommend rephrase it and use story telling technique to clarify and connect all the information and paragraphs. In addition I suggest to delete the phrase “which is important for policy maker to set preventive strategies.” in the end of the introduction and add it to discussion section.Author’s response: We tried to rephrase the paragraph accordingly and the phrase “which is important for policy maker to set preventive strategies” had been removed in the introduction section and added to discussion section. The revision is found in the manuscript. Methods sessionQuestion and comments #7: Indicate if a review protocol exists, if and where it can be accessed , and, if available, provide registration information including registration number.Author’s response: The review protocol was prepared before a review is started. It is registered at PROSPERO international data base with PROSPERO registration number (PROSPERO 2020: CRD42020167734). These revisions are found on the manuscript. Question and comments #8: It is not clear about the publication years of the articles selected, language, and publication statusAuthor’s response: Five articles published from year 2013-2019 and two unpublished articles in Addis Ababa and Haramaya University online repository reported in English language was selected for analysis. These revisions are found in the manuscript Question and comments #9: I would like to recommend you to change the expression “poor quality” for the reason, I mean, which was the problem to not include it? Study design? Sample size? Not clear outcomes?Author’s response: It is to mean that article with JBI critical appraisal score less than 50% was excluded. The word “poor quality” is replaced with the word article with JBI critical appraisal score less than 50%Question and comments #10: In phrase “the prospective follow up study reporting the prevalence of adverse birth outcomes or and a minimum of one contributing factors for adverse birth outcomes conducted in Ethiopia were included”. Did you establish a minimum and maximal follow up period? Let this information clear.Author’s response: The minimum and maximum follow up period was not established. Question and comments #11: Please replace still births to stillbirthsAuthor’s response: The word still births has been replaced to stillbirths on page 8 (outcome measurement section).Question and comments #12: Please replace soft wear to software in the phrase “The extracted data were transferred to STATA version 14 statistical soft wear for meta-analysis”Author’s response- The word soft wear has been replaced to software on. Results sessionQuestion and comments #13- In the first paragraph “Three hundred seventy seven articles were retrieved using a search strategy from PubMed, Cochrane Library, Google Scholar, SCOPUS, Web of Science and PsycINFO”, you didn’t mentioned the Addis Ababa and Haramaya University online repository.Author’s response: Accepting the comment and the phrase Addis Ababa and Haramaya University online repository are added on page 9, line 3 (result section).Question and comments #14: I highly recommend to add the references into the tables to allow the reader find the articles easier.Author’s response: The references are cited in each included studies in table 1. Question and comments #15: Table 4 was included Maternal age <35 years but in the text in socio-demographic factors session “Addis Ababa indicated that the odds of having adverse birth outcomes among diabetics women age less than 30 years old was 3.47” please clarify this point for us.Author’s response: it is type error and corrected as……women age less than 30 years old in table 4.Question and comments #16: Your results bring more than the purposed by the aim of your paper. “Therefore, this systematic review and meta-analysis is the first aimed to estimate the pooled prevalence of adverse birth outcomes and associated factors among diabetic pregnant women in Ethiopia which is important for policy maker to set preventive strategies.” You actually brings the prevalence, pregnancy related risk factors and the adverse birth outcomes and during your data presentation in table 1, I expected that the pregnancy related risk factors should be present on it.Author’s response: Pregnancy related risk factors are presented in table 1Question and comments #17: Another concern is about the measure units in the table, please review it. I suggest to fix two decimal cases as standard to the table values.Author’s response: The decimal case is changed to two decimal points in each table.Discussion SessionQuestion and comments #18: In order to improve the discussion I highly recommend the use of storytelling techniques to help you to delineate the findings and discuss it with the already included data. In the first phrase is interesting to add the mainly findings in an easy and quickly summarization to the reader follow the discussion topics of each findings and its possible explanation.Author’s response: The main finding of the study is written in the first phase of the paragraph and rearrangement was done; the second paragraph taken next to the first sentence and the paragraph next to the first sentence is deleted. The discussion is written based on an included data.Question and comments #19: It is of paramount importance to perform a major English revisionAuthor’s response: Sure! From repeated proof-reading of the manuscript, we found several grammatical errors, interlinings, police titles, punctuation errors, wordings and spelling errors. Therefore, finding our colleague who has Master of Arts in English, we have tried our best to thoroughly copyedit the manuscript for English language usage. These changes are found throughout the revised version manuscript. Conclusion SessionQuestion and comments #20: The conclusion should address the aim.AIM: “To estimate the pooled prevalence of adverse birth outcomes and associated factors among diabetic pregnant women in Ethiopia which is important for policy maker to set preventive strategies? ”Conclusion: “According to this systematic review and meta-analysis, the pooled prevalence of adverse birth outcome among diabetic women in Ethiopia was high. Unable to read and write, maternal age less than 30 years old, gestational age less than 37 completed weeks, previous adverse birth outcomes and no ANC follow up was significantly associated with adverse birth outcomes.”I would like to rephrase the conclusion to further clarification. The phrase “Ethiopia was high” comparing to? I suggest to replace by the %.In addition, again I will insist that your data brings not only the prevalence of adverse birth outcomes, pregnancy related risk factors, but the adverse birth outcomes, and it should be addressed in the conclusion and in the aim.Author’s response: In conclusion section the word “high” replaced by 5.3%The following statement (recommendation) was added based on the finding. “So, early screening of diabetes during pregnancy and follow up is important to alleviate the burden of maternal and neonatal adverse birth outcomes. In addition, concern should be given in improving antenatal follow up.” With regards!Demeke Mesfin Belay  21 Oct 2020Adverse Birth Outcome and associated factors among Diabetic Pregnant Women in Ethiopia; Systematic review and Meta-analysisPONE-D-20-26756R1Dear Dr. Belay,We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org.An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at onepress@plos.org.If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact Kind regards,Frank T. SpradleyAcademic EditorPLOS ONEReviewers' comments:Reviewer's Responses to QuestionsComments to the Author1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.Reviewer #1: All comments have been addressed**********2. Is the manuscript technically sound, and do the data support the conclusions?The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. Reviewer #1: Yes**********3. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes**********4. Have the authors made all data underlying the findings in their manuscript fully available?PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.The Reviewer #1: Yes**********5. Is the manuscript presented in an intelligible fashion and written in standard English?PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.Reviewer #1: Yes**********6. Review Comments to the AuthorPlease use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. Reviewer #1: The paper is appropriate and has been revised according to the reviewer's suggestions. The results are relevant and will contribute to the dissemination of knowledge in this important area of health.**********what does this mean?). If published, this will include your full peer review and any attached files.7. PLOS authors have the option to publish the peer review history of their article (If you choose “no”, your identity will remain anonymous but your review may still be made public.Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.Reviewer #1: No 23 Oct 2020PONE-D-20-26756R1 Adverse Birth Outcome and associated factors among Diabetic Pregnant Women in Ethiopia; Systematic review and Meta-analysis Dear Dr. Belay:I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department. onepress@plos.org.If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information please contact plosone@plos.org. If we can help with anything else, please email us at Thank you for submitting your work to PLOS ONE and supporting open access. Kind regards, PLOS ONE Editorial Office Staffon behalf ofDr. Frank T. Spradley Academic EditorPLOS ONE


Scientific Reports 10.1038/s41598-018-27190-x, published online 12 June 2018Correction to: In this Article, the legend of Figure 2 is incorrect:a) Placental villous explants n = 10; (b) Amnion explants, n = 10; (c) Tonsillar explants n = 5; (d) Cervical explants n = 6; (e) PPP from healthy donors n = 52; (f) Amniotic fluid from 3 donors (g) T cells n = 6; (h) Monocytes n = 6. *Indicates significant difference p < 0.05 between surface and encapsulated cytokines.”“Distribution of cytokines between the surface and the inner volume of EVs. Fractions of total EV-associated cytokines ± SEM. Samples collected as in Fig. 1. (should read:a) Placental villous explants n = 10; (b) Amnion explants, n = 10; (c) Tonsillar explants n = 5; (d) Cervical explants n = 6; (e) PPP from healthy donors n = 52; (f) T cells n = 6; (g) Monocytes n = 6; (h) Amniotic fluid from 3 donors. *Indicates significant difference p < 0.05 between surface and encapsulated cytokines.”“Distribution of cytokines between the surface and the inner volume of EVs. Fractions of total EV-associated cytokines ± SEM. Samples collected as in Fig. 1. .For T cells  and monocytes  fewer cytokines were on the surface of EVs, whereas for both types of cells EV-associated cytokines were predominantly inside the vesicles (25 and 20 respectively).”should read:“In contrast to plasma, in amniotic fluid out of all EV-associated cytokines only two, IL-17 and IFN-γ, were preferentially on the surface of EVs and only small fractions of another three, IL-1α, IL-22, and ITAC, were present on the surface of EVs; whereas 27 other cytokines were almost exclusively inside EVs .For T cells  and monocytes  fewer cytokines were on the surface of EVs, whereas for both types of cells EV-associated cytokines were predominantly inside the vesicles (25 and 20 respectively).”


FUT2) and FUT3 genes are related to IBD. This study aimed to investigate whether these genes correlated with the susceptibility to AS. Questionnaires of 673 patients with AS, and peripheral blood specimens of the patients and 687 healthy controls were collected. FUT2 and FUT3 genes were genotyped using the SNPscan method. Frequency differences of the genes at different levels, haplotypes, and interactions were analyzed. No frequency differences were found between the cases and the controls in all the genotypes and the alleles of rs1047781, rs1800028, rs1800030, and rs812936. For rs28362459, a significant difference in allele frequencies was observed in the total participants between the groups . The frequencies of haplotypes TT (rs812936–rs28362459)  and TG (rs812936–rs28362459)  in the total participants, and TG (rs812936–rs28362459) in the female subgroup  showed significant differences between the cases and the controls. No frequency differences at the phenotypic level were found. Two-factor interactions were observed between rs28362459-TG and age, rs28362459-TG and sex, rs28362459 and rs1047781, and the Lewis and secretor status. Rs28362459-G was related to some aggravated symptoms of AS . These findings indicated that FUT3 polymorphisms were associated with human predisposition to AS at the allele and haplotype level. Rs28362459-G might decrease the susceptibility to AS, but aggravate relevant symptoms.Many susceptibility genes of inflammatory bowel disease (IBD) are associated with ankylosing spondylitis (AS). Fucosyltransferase 2 ( Ankylosing spondylitis (AS) is a serum-negative connective tissue disease characterized by back pain and rigidity. Its etiology involves genetic, environmental, infectious, and immune factors. A number of studies have proved that genetic factors play a significant role in the pathogenesis of the disease. At least 36 susceptibility genes of AS have been found so far , among wSome studies suggested that about 50%–60% of patients with AS also suffered from intestinal inflammation , 8, and FUT2) gene encodes α1,2-L-fucosyltransferase, which catalyzes the biosynthesis of type-1 H (Led), a blood group antigen, using a type-1 precursor (Lec) and fucose. Type-1 H is also a precursor of several other blood group antigens, such as type-1 A or type-1 B. An individual having functional FUT2 (Se) is called a secretor, whose fluids and secretions may contain soluble A, B, and H antigens. Otherwise, an individual with two null FUT2 alleles (se) is called a non-secretor, who cannot synthesize these antigens. The human FUT3 gene encodes α1,3/4-L-fucosyltransferase, which catalyzes the synthesis of Lea antigen in non-secretors using Lec and fucose, or catalyzes the synthesis of Leb in secretors using type-1 H and fucose. Therefore, non-secretors with functional FUT3 (Le) exhibit the Le(a+b-) serotype, secretors with Le exhibit the Le(a-b+) serotype, and individuals with two null FUT3 alleles (le) present the Le(a-b-) serotype despite their secretor status  of the cases and controls were comparable (P > 0.05). Raw data of genotyping outcomes were partly provided in A total of 925 patients with AS were enlisted and 673 of them  agreed to join this study eventually. Meanwhile, 687  of 892 eligible healthy controls consented to participate (control/case ≈ 1.021). The male/female ratio  G/T = 0.782; 95% CI, 0.650–0.941; Power = 0.8] (Pcorrected > 0.05). In the male and female subgroups, all the five SNPs showed no significant differences in allele frequency between the cases and the controls . These suggested that the polymorphisms of rs28362459 were probably associated with human susceptibility to AS, and the allele rs28362459-G might be a protective factor for AS.The genotype frequencies of the five SNPs included in this study showed no differences between the cases and the controls, both in the total participants and in either sex subgroup  . At the r = 0.8] , S2 Fig.χ2 = 5.663, Ppermutation = 0.039; Power = 0.7; D' = 0.931) and TG (rs812936–rs28362459) . A significant difference in the frequencies of haplotype TG (rs812936-rs28362459) was also found between the two groups in the female subgroup   (= 0.916) . These radjusted = 0.071; 95% CI, 0.005–0.980; Pcorrected = 0.048), and rs28362459-TG and sex . In the male subgroup, a multiplicative interaction was observed between rs28362459-TG and age . In the female subgroup, no multiplicative interactions were found . Moreover, additive interactions were observed between rs1047781 and rs28362459 in the total participants , the male subgroup , and the female subgroup  (P > 0.05).In the analyses of two-factor interaction, multiplicative interactions were found in the total participants between rs28362459-TG and age (OR1–7.251) . No multPcorrected > 0.05). Similarly, no differences were observed between the patients and the controls in terms of the frequencies of the Lewis status  and the Lewis serotype   .Pcorrected > 0.05). Additive interactions were found between the Lewis status and the secretor status in the total participants , the male subgroup , and the female subgroup  (P > 0.05). These findings suggested that the phenotypes of FUT2 and FUT3, and their co-determined Lewis serotypes, might not correlate with the predisposition to AS.No multiplicative interactions were found at phenotypic level in all the factors  . No multPcorrected > 0.05). However, at the item level, the results revealed that rs1800030-A was related to an alleviated morning stiffness , while rs28362459-G was related to a severer limitation with regard to standing without support  among patients with AS . Lewis-positive (Le) patients suffered less functional loss compared with Lewis-negative (le) patients in terms of BASFI 6  and bending forward from the waist   and BASFI 2  compared with the Le(a-b-) patients. In addition, the Le(a+b-) and Le(a-b+) patients also suffered less than the Le(a-b-) ones in regard to reaching up to a high shelf  and climbing 12–15 steps independently  (Pcorrected > 0.05). These results indicated that the polymorphisms of FUT2 and FUT3 were likely to be associated with the symptoms of AS, and rs28362459-G might aggravate relevant symptoms.To explore the links between the gene polymorphisms and the clinical manifestations of AS, association analyses were conducted at the gene and phenotypic levels. No associations were found between the gene polymorphisms and the BASFI/BASDAI  . In liner = 0.3) . No signFUT2/FUT3 and IBD [FUT3 polymorphisms were associated with the susceptibility to AS, and rs28362459-G might be a protective factor for AS. These findings suggested that some pathogenic factors might attach to Lewis antigens in the development of AS, and the lack of these antigens might block the process. This was consistent with the report that the adhesion of Helicobacter pylori to gastric mucosa correlated closely with Leb in the host body, and the binding of Escherichia coli to the epithelial cells of intestinal mucosa needed a glycosylation structure [Helicobacter pylori were commonly much lower in non-secretors than in secretors [In view of a large degree of overlap between the susceptibility genes of IBD and AS , 12, 13, and IBD , 20, 21,tructure , 18. Thiecretors , 28.FUT3 gene, indicating associations between the gene and AS at the haplotype level. These were consistent with the results at the allele level. Although no reports on the roles of these haplotypes can be found so far, the following points may provide a rational explanation for the results: It is clear the haplotype TG (rs812936–rs28362459) is one of the determinants of Lewis-negative status; and it is supposed that the haplotype TT (rs812936–rs28362459) may influence the structure and quantity of Lewis antigens.The results of the haplotype analyses revealed significant differences between the cases and the controls in the frequencies of haplotypes TT (rs812936–rs28362459) and TG (rs812936–rs28362459). Both the SNPs located in This study discovered a potential susceptibility gene for AS, providing fresh data for exploring the etiology of AS. Meanwhile, this was the first report of a link between a blood group gene and AS, leading to new developments in the functional study of human blood groups. Although Shinebaum reported associations between ABO antigens of non-secretors and host susceptibility to spondyloarthropathies , the resFUT3 polymorphisms and age was possibly related to the influence of age on the expression of Lewis antigens, and the influence might also be associated with the maturity of human gut microbiota [No significant differences were found between the cases and the controls in the frequencies of secretor status, Lewis status, and Lewis serotype. However, interactions on an additive scale were found between the Lewis status and the secretor status. The interactions might reflect the fact that the two factors jointly determined the type of Lewis HBGAs, which were likely the real molecules participating in the pathogenesis of AS. Moreover, the interaction between the crobiota , 19.FUT3 and AS at the phenotypic level were as follows. First, both FUT2 and FUT3 directly encode fucosyltransferase, which may have other biological functions besides determining the human secretor status and Lewis antigens. These functions may play varied roles in the development of AS. Second, the synthesis of the Lewis HBGAs complex, such as ALeb, is also influenced by FUT1 and ABO genes, besides being controlled by FUT3. Finally, the Lewis serotypes in this study were inferred only from genotyping results, with no verifications using serological and salivary tests due to specimen limitations.The possible reasons for not finding correlations between FUT3 might play complicated roles in the pathogenesis of AS. A probable cause for the results was that rs28362459-G might bring about multiple changes in human gut microbiota, and further affect host immune functions. This could be similar to the situation in which the intestinal flora in a non-secretor’s colon changed significantly in both structure and function among patients with CD [This study found multiple associations between rs28362459 and the clinical manifestations of AS at the genetic and phenotypic levels. Generally speaking, rs28362459-G, Lewis-negative status, and Le(a-b-) serotype might correlate with several aggravated disease indexes. These demonstrated to some extent that disease activity, functional impairments, and imaging changes in AS were also highly heritable . As ment with CD , 33.FUT2 and FUT3 genes, but did not include FUT1 and ABO genes, which were also related to HBGAs. Therefore, the results of this study had certain one-sidedness. Moreover, due to the limited sample size, the power of analysis was affected to some extent for some subgroups. Due to the limited quality of questionnaire data, some analyses could not be carried out, such as the correlations between FUT3 and relevant laboratory variables. Due to the limited size of untreated cases, the combination of treated and untreated cases, without statistical difference in nonparametric tests, was used in the analyses of associations between the gene polymorphisms and disease indexes. This might bring some bias.As with other case–control studies, this study also had some shortcomings. Correlations were found only between the genes and AS, but relevant mechanisms were not explored. This study involved only FUT2 or FUT3. The findings may help in deepening the understanding of the associations between the FUT3 gene and AS, and also in developing new treatment strategy for AS.To verify the findings of this study and further uncover the underlying mechanisms, researchers can investigate the compositional and functional characteristics of intestinal flora among patients with AS in the future. Furthermore, they can establish proper animal models of AS and explore the roles of HBGAs by blocking the expression of FUT3 gene polymorphisms correlated with human susceptibility to AS, both at the allele and haplotype level. Rs28362459-G might decrease the susceptibility, but enhance part of disease indexes of AS. This study highlighted the probability of wide associations between the blood group antigens and human autoimmune diseases.S1 Checklist(DOCX)Click here for additional data file.S1 Fig(PDF)Click here for additional data file.S2 Fig(PDF)Click here for additional data file.S1 Table(PDF)Click here for additional data file.S1 File(PDF)Click here for additional data file.S2 File(PDF)Click here for additional data file.S1 Database(XLSX)Click here for additional data file.