Paediatric and perinatal epidemiology最新文献

{"title":"Neonatal Adverse Outcomes in Métis Children in Alberta, Canada: A Retrospective Cohort Study.","authors":"Jesus Serrano-Lomelin, Reagan Bartel, Ashton Anderson, Kelsey Bradburn, Susan Crawford, Jeffrey A Bakal, Amy Colquhoun, Anne Hicks, Matthew Hicks, Manoj Kumar, Rhonda J Rosychuk, Alvaro Osornio-Vargas, Radha Chari, Maria B Ospina","doi":"10.1111/ppe.70166","DOIUrl":"10.1111/ppe.70166","url":null,"abstract":"<p><strong>Background: </strong>Composite indicators of neonatal morbidity specific to Métis populations in Canada are lacking.</p><p><strong>Objectives: </strong>To estimate the incidence of neonatal morbidity and neonatal death among Métis neonates in Alberta, and to identify maternal and neonatal factors associated with neonatal morbidity.</p><p><strong>Methods: </strong>Population-based retrospective cohort study including all singleton live births to Métis mothers in Alberta between April 2006 and March 2016. Hospital discharge data were used to evaluate the Neonatal Adverse Outcome Indicator (NAOI), which comprises a set of newborn medical complications and neonatal death. We estimated overall and annual NAOI incidence proportions and overall neonatal mortality. Multilevel regression models were used to estimate adjusted risk ratios (aRRs) with 95% confidence intervals (CIs) for maternal and neonatal characteristics associated with NAOI.</p><p><strong>Results: </strong>Among 7853 neonates, the overall NAOI incidence proportion was 10.1% (95% CI 9.5, 10.8), ranging annually from 7.7% (95% CI 6.1, 9.7) to 11.9% (95% CI 8.1, 17.2). The most common conditions were respiratory conditions originating in the perinatal period (4.8%, 95% CI 4.3, 5.3) and birth trauma (3.4%, 95% CI 3.0, 3.8). The overall neonatal mortality rate was 2.9 per 1000 live births (95% CI 1.9, 4.4). Increased risk of NAOI was associated with pre-pregnancy disease (aRR 1.27, 95% CI 1.03, 1.51), pregnancy-related disease (aRR 1.92, 95% CI 1.65, 2.18), assisted vaginal delivery (aRR 2.52, 95% CI 2.09, 2.94), caesarean delivery (aRR 1.23, 95% CI 1.04, 1.41), male sex (aRR 1.27, 95% CI 1.09, 1.42), preterm birth (aRR 4.36, 95% CI 3.71, 5.00) and any congenital malformation (aRR 2.71, 95% CI 1.87, 3.56).</p><p><strong>Conclusions: </strong>The incidence of neonatal morbidity among Métis neonates in Alberta highlights the importance of continued surveillance using standardised indicators. Incorporating NAOI into perinatal and obstetric care may inform culturally responsive improvements in care.</p>","PeriodicalId":19698,"journal":{"name":"Paediatric and perinatal epidemiology","volume":" ","pages":"733-744"},"PeriodicalIF":2.7,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13522652/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148318298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Association Between Foetal Brain and Body Size Mid-Gestation and Neurodevelopmental Disorders in Childhood.","authors":"Mads Langager Larsen, Gorm Greisen, Lone Krebs, Christina Engel Hoei-Hansen, Olav Bjørn Petersen","doi":"10.1111/ppe.70159","DOIUrl":"10.1111/ppe.70159","url":null,"abstract":"<p><strong>Background: </strong>Smallness for gestational age and reduced head circumference at birth are consistently associated with later neurodevelopmental disorders (NDD), but it is unclear whether similar associations are present at foetal biometry in mid-gestation.</p><p><strong>Objectives: </strong>To investigate associations between second-trimester foetal biometric measurements and later NDD.</p><p><strong>Methods: </strong>We conducted a population-based cohort study using data from routine second-trimester ultrasound scans (gestational weeks 18-21) in Denmark. We included all singleton euploid live births from 2008 to 2015. Foetal biometrics included head circumference, biparietal diameter (BPD), abdominal circumference (AC), femur length, estimated foetal weight (EFW), and the head-abdomen ratio. NDD comprised cerebral palsy (CP), epilepsy, intellectual disability, and autism spectrum disorders (ASD). Children were followed from birth until diagnosis, death, emigration, or 31 December 2022. Associations were examined using multivariable Cox proportional hazards models, and cumulative incidence through age 10 years was estimated accounting for death as a competing risk. Adjusted mean differences in biometric Z-scores were examined using multivariable linear regression.</p><p><strong>Results: </strong>Among 337,028 children, 13,414 (4.0%; 69.7% males) were diagnosed with at least one NDD. Larger BPD was associated with higher hazards of epilepsy, intellectual disability, and ASD. Larger AC and EFW were associated with lower hazard of intellectual disabilities. Individuals with epilepsy, ASD, and intellectual disabilities had slightly larger mean BPD Z-score at their second-trimester scans, compared to children without NDD. Furthermore, smaller HC was associated with lower hazards and cumulative incidence of epilepsy, whereas shorter FL was associated with higher hazards of CP and epilepsy.</p><p><strong>Conclusions: </strong>Mid-gestation head size did not follow the expected risk pattern. These findings propose a rethinking of the relationship between restricted brain growth and neurodevelopmental impairment, suggesting that atypical early brain development may be reflected in accelerated rather than reduced growth, or that restricted growth-related causes of NDD act later in pregnancy.</p>","PeriodicalId":19698,"journal":{"name":"Paediatric and perinatal epidemiology","volume":" ","pages":"745-755"},"PeriodicalIF":2.7,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13522650/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147974426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Social Inequalities in Infant Mortality Related to Congenital Anomalies: A Population-Based Register Study.","authors":"Bermet Amirova, Nathalie Lelong, Marine Wojciechowski, Marie-Victoire Sénat, Babak Khoshnood, Jennifer Zeitlin, Isabelle Monier","doi":"10.1111/ppe.70162","DOIUrl":"10.1111/ppe.70162","url":null,"abstract":"<p><strong>Background: </strong>Infant mortality has recently increased in France, especially in deprived areas. Congenital anomalies (CA) are a major cause of infant mortality and could contribute to these trends.</p><p><strong>Objectives: </strong>This study aimed to investigate socio-spatial inequalities in infant mortality associated with CA. It also examined socio-spatial differences in antenatal detection.</p><p><strong>Methods: </strong>We included all live births ≥ 22 weeks with CA from the Paris Registry of CA (remaPAR). Births are linked to infant deaths < 1 year using vital statistics records. A case-population design was applied to assess the association between an area-based deprivation score, assigned at the smallest census tract level (IRIS) of the mother's place of residence, and risks of infant death and live birth with CA. In the absence of data on births at the IRIS level, we used an aggregated population comparison group of children < 2 years old in 2019-2022 census data. We computed unadjusted odds ratios (OR) by comparing the distribution of the area-based score in quartiles in the case and census comparison populations. We also compared antenatal detection of CA by deprivation quartile.</p><p><strong>Results: </strong>The study included 2539 live births, resulting in 81 infant deaths. The proportions of infant deaths with CA were 39.5% and 16.0% in the most and least deprived quartiles, respectively, yielding an OR of 2.43 (95% confidence interval [CI] 1.28, 4.63). For live births with CA, these percentages were 29.7% and 22.0% with an OR of 1.34 (95% CI 1.20, 1.49). No variation across quartiles was observed in antenatal detection of CA, with a detection rate of 56.0% for live births and 85.2% for infant deaths. First-trimester ultrasound use was high (90.5%) but was lower in the most compared to the least deprived quartile (87.8% and 93.9%, respectively); however, second-trimester ultrasound use was similar across quartiles.</p><p><strong>Conclusions: </strong>Area-based deprivation was associated with higher risks of infant mortality and live birth with CA, but not antenatal detection of CA. These results raise questions about differences in CA aetiology and decision-making about termination of pregnancy after CA detection.</p>","PeriodicalId":19698,"journal":{"name":"Paediatric and perinatal epidemiology","volume":" ","pages":"694-699"},"PeriodicalIF":2.7,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13522641/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148138622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Re: Do Birthweight-For-Gestational Age Centiles Predict Serious Neonatal Morbidity and Neonatal Mortality?","authors":"Sid John, K S Joseph, John Fahey, Shiliang Liu, Sarka Lisonkova, Michael S Kramer","doi":"10.1111/ppe.70183","DOIUrl":"10.1111/ppe.70183","url":null,"abstract":"","PeriodicalId":19698,"journal":{"name":"Paediatric and perinatal epidemiology","volume":" ","pages":"769-770"},"PeriodicalIF":2.7,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13522643/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148562571","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Infertility and Risk of Congenital Anomalies: A Population-Based Cohort Study.","authors":"Bailey Milne, Susan B Brogly, Jonas Shellenberger, Maria P Velez","doi":"10.1111/ppe.70184","DOIUrl":"10.1111/ppe.70184","url":null,"abstract":"<p><strong>Background: </strong>Fertility treatments have been associated with an increased risk of congenital anomalies. Most studies have compared births conceived through fertility treatment with unassisted conceptions; consequently, these estimates reflect the combined effects of fertility treatment and the underlying infertility, potentially resulting in confounding by indication.</p><p><strong>Objectives: </strong>To estimate the association between infertility, independent of fertility treatment, and the risk of congenital anomalies.</p><p><strong>Methods: </strong>This population-based cohort study included all live births and stillbirths at ≥ 20 weeks' gestation to women aged 15-50 in Ontario, Canada, 2006-2021. Infertility without treatment was defined as a history of one or more infertility consultations with a physician within 2 years before conception, in the absence of fertility treatment. Modified Poisson regression generated relative risks (RR) adjusted for maternal age, income quintile, rurality, pre-existing comorbidities, and smoking, alcohol use, and substance use during pregnancy.</p><p><strong>Results: </strong>Of the 1,415,324 deliveries, the prevalence of congenital anomalies was 5.3% in unassisted conception and 5.9% among births to women with infertility who did not use fertility treatment. A small increase in risk was observed for any congenital anomaly (RR 1.12, 95% confidence interval [CI] 1.09, 1.14). Among organ system anomalies, the highest relative risks were observed for eye anomalies (0.11% vs 0.14%; RR 1.22, 95% CI 1.03, 1.45) and ear, face, and neck anomalies (0.06% vs 0.08%; RR 1.19, 95% CI 1.05, 1.35). Among specific anomalies, the highest relative risk was observed for other penile malformations (0.03% vs 0.04%; RR 1.41, 95% CI 1.09, 1.83).</p><p><strong>Conclusions: </strong>Although the overall risk of congenital anomalies was low, infants born to women with infertility who did not use fertility treatment had small increased risks of any congenital anomaly, selected organ system anomalies, and specific anomalies compared with infants born from unassisted conceptions.</p>","PeriodicalId":19698,"journal":{"name":"Paediatric and perinatal epidemiology","volume":" ","pages":"700-708"},"PeriodicalIF":2.7,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13522657/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148674033","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Medication Exposure Definitions in Perinatal Pharmacoepidemiology: Implications for Pregnancy Studies.","authors":"Gabra Nohmie, Anick Bérard, Anton Pottegård, Mette Bliddal","doi":"10.1111/ppe.70158","DOIUrl":"10.1111/ppe.70158","url":null,"abstract":"<p><strong>Background: </strong>Exposure definitions in real-world pregnancy studies vary across studies, data sources, treatments and outcomes, yet their impact on prevalence estimates remains unexamined.</p><p><strong>Objectives: </strong>To identify the most used exposure definitions during the 1st trimester and evaluate their impact on prevalence estimates: METHODS: We reviewed 400 randomly selected articles on medication use during pregnancy to identify exposure definitions. Using Danish health registers (1997-2024) and the Québec Pregnancy Cohort (1998-2015), we analysed chronic, as-needed, and acute medication use. Prevalence (per 1000) was calculated per definition, including: (1) ≥ 1 or (2) ≥ 2 filled prescriptions during 1st trimester; filled ≥ 1 prescription anytime between the 1st trimester or (3) 30 days, (4) 60 days, (5) 90 days, (6) 6 months before conception; filled a prescription during 1st trimester or before conception, (7) assuming 1 daily defined dose per day or (8) prescribed days overlapping 1st trimester. Trends across cohorts and medications were compared.</p><p><strong>Results: </strong>We analysed 1,524,075 pregnancies in Denmark and 229,000 in Québec, Canada. The most common exposure definitions identified from the literature were Definition 1 (83%), followed by Definition 3 (13%). Prevalence varied across definitions, with differential impacts depending on medication and type of use. Definition 6 (1st trimester or within the 6 months before conception) yielded the highest prevalence; Definition 2 (≥ 2 fills in 1st trimester) the lowest. Broader time-windows of exposure increased prevalence, with variation by medication. The prevalence of medication use, whether chronic or acute, showed less variation across definitions than that of as-needed medication.</p><p><strong>Conclusions: </strong>Medication exposure prevalence varied by definition and medication. Using ≥ 1 filled prescriptions in the 1st trimester yielded prevalence estimates comparable to those from more complex definitions, supporting its use as a pragmatic standard. Sensitivity analyses and transparent reporting of exposure definition are essential to ensure replicability and critical appraisal.</p>","PeriodicalId":19698,"journal":{"name":"Paediatric and perinatal epidemiology","volume":" ","pages":"681-690"},"PeriodicalIF":2.7,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13522648/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148056093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mortality Risk Between Ages 11 and 22 Years Among Young People With Neurodisability in England: A National Cohort Study Using Linked Health and Education Data.","authors":"Louise Macaulay, Jennifer Saxton, Tamsin Ford, Stuart Logan, Katie Harron, Ruth Gilbert, Ania Zylbersztejn","doi":"10.1111/ppe.70178","DOIUrl":"10.1111/ppe.70178","url":null,"abstract":"<p><strong>Background: </strong>Mortality risk rises from childhood into early adulthood. Young people with neurodisability (neurological conditions causing functional limitations) may be particularly vulnerable during the transition from paediatric to adult services.</p><p><strong>Objectives: </strong>To estimate all-cause and cause-specific mortality risk between the ages of 11-22 years in young people with and without neurodisability in England.</p><p><strong>Methods: </strong>In this national cohort study, we used linked health and education records from ECHILD to follow pupils from age 11 between 2008-09 and 2014-15 to age 22. Neurodisability was identified from hospital admission records before age 11, likely capturing more severe conditions, and supplemented with education data for intellectual disability and autism. Gender-specific crude cumulative mortality risk and relative differences were estimated using Kaplan-Meier curves and Cox models, with cause-specific risk estimated using competing-risks methods.</p><p><strong>Results: </strong>Among 3,601,180 young people, 143,864 (4.0%) had neurodisability. Between the ages of 11-22, 5565 (0.15%) died; 24% had neurodisability. By age 22, cumulative mortality risk was 1.6% (95% confidence interval [CI] 1.4, 1.8) among females with neurodisability versus 0.14% (95% CI 0.13, 0.15) among peers without neurodisability (hazard ratio [HR] 13.88, 95% CI 12.55, 15.35), an absolute risk difference of 1.5% (95% CI 1.3, 1.6). Among males with neurodisability, cumulative risk was 1.3% (95% CI 1.2, 1.4) versus 0.28% (95% CI 0.27, 0.29; HR 5.34, 95% CI 4.94, 5.78) among peers, an absolute risk difference of 1.0% (95% CI 0.9, 1.1). Most deaths among those with neurodisability were from medical causes, with cumulative risks of 1.5% (95% CI 1.3, 1.6; HR 25.87, 95% CI 23.03, 29.07) in females and 1.1% (95% CI 0.96, 1.2; HR 14.70, 95% CI 13.29, 16.26) in males by age 22.</p><p><strong>Conclusions: </strong>Young people with neurodisability had a higher mortality risk than peers between ages 11-22, largely from medical causes, with variation by gender and neurodisability subgroup.</p>","PeriodicalId":19698,"journal":{"name":"Paediatric and perinatal epidemiology","volume":" ","pages":"756-766"},"PeriodicalIF":2.7,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13522658/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148412545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Re: Do Birthweight-For-Gestational Age Centiles Predict Serious Neonatal Morbidity and Neonatal Mortality?","authors":"Maajid Mohi Ud Din Malik, Rajesh Prasad Jayaswal, Abhay Saraf","doi":"10.1111/ppe.70182","DOIUrl":"10.1111/ppe.70182","url":null,"abstract":"","PeriodicalId":19698,"journal":{"name":"Paediatric and perinatal epidemiology","volume":" ","pages":"767-768"},"PeriodicalIF":2.7,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13522647/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148605982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Maternal Haemoglobin and Stillbirth Risk: Implications for Policy and Practice.","authors":"Melissa F Young","doi":"10.1111/ppe.70165","DOIUrl":"10.1111/ppe.70165","url":null,"abstract":"","PeriodicalId":19698,"journal":{"name":"Paediatric and perinatal epidemiology","volume":" ","pages":"720-722"},"PeriodicalIF":2.7,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13522646/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148212135","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Maternal Haemoglobin and Haematocrit During Pregnancy and Stillbirth Risk: A Prospective, Population-Based Birth Cohort Study.","authors":"Shuangying Li, Nina Dempsey, Shen Gao, Shaofei Su, Shuanghua Xie, Zhengyang Yao, Minhui Hu, Juan Li, Zhan Li, Enjie Zhang, Jianhui Liu, Hao Xing, Jinghan Yu, Shaowen Wu, Wentao Yue, Ruixia Liu, Alexander E P Heazell, Chenghong Yin","doi":"10.1111/ppe.70144","DOIUrl":"10.1111/ppe.70144","url":null,"abstract":"<p><strong>Background: </strong>Maternal anaemia is a public health issue globally, associated with adverse maternal and neonatal outcomes. However, less is known about the effects of high haemoglobin (Hb) and haematocrit (Hct) on the risk of stillbirth.</p><p><strong>Objectives: </strong>We assessed the dose-response effects of dynamic changes in maternal Hb and Hct across all trimesters on stillbirth risk.</p><p><strong>Methods: </strong>This study was based on the prospective, longitudinal, population-based China birth cohort study (CBCS) between 2018 and 2022, including 142,715 women with live births or stillbirths delivered at ≥ 20 weeks' gestation. The modified Poisson regression models were used to assess the association between Hb/Hct, haemodilution status across three trimesters and stillbirth.</p><p><strong>Results: </strong>Over a fifth (23.6%) of pregnant women had anaemia at least once during pregnancy. Maternal anaemia increased the risk of stillbirth. The adjusted risk ratio (aRR) for Hb at 70-99 g/L (moderate anaemia) was 2.45, 95% confidence interval (CI) 1.26, 4.76 and aRR for Hct < 33% (anaemia) was 1.63 (95% CI 1.12, 2.38) in the first trimester. Interestingly, a U-shaped association between Hb/Hct and stillbirth was observed, and high Hb/Hct levels in any of the three trimesters were related to increased stillbirth risk. Excessive haemoglobin dilution/haemoglobin concentration across trimesters was also associated with higher stillbirth risk, especially from the first to the second trimesters, with aRRs of 1.86 (95% CI 1.15, 3.01) and 3.34 (95% CI 2.08, 5.37), respectively.</p><p><strong>Conclusions: </strong>Considering the U-shaped association between Hb/Hct levels and stillbirth, clinical vigilance is necessary at both low- and high-extremes of Hb/Hct and physiological haemodilution metrics in mid-to-late pregnancy for improved pregnancy outcomes.</p>","PeriodicalId":19698,"journal":{"name":"Paediatric and perinatal epidemiology","volume":" ","pages":"709-719"},"PeriodicalIF":2.7,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13522651/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147593559","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}