Severe Maternal Morbidity and Mental Health Hospitalizations or Emergency Department Visits.

Importance: Severe maternal morbidity (SMM) can have long-term health consequences for the affected mother. The association between SMM and future maternal mental health conditions has not been well studied. Objective: To assess the association between SMM in the first recorded birth and the risk of hospitalization or emergency department (ED) visits for a mental health condition over a 13-year period. Design, Setting, and Participants: This population-based retrospective cohort study used data from postpartum individuals aged 18 to 55 years with a first hospital delivery between 2008 and 2021 in 11 provinces and territories in Canada, except Québec. Data were analyzed from January to June 2023. Exposure: SMM, defined as a composite of conditions, such as septic shock, severe preeclampsia or eclampsia, severe hemorrhage with intervention, or other complications, occurring after 20 weeks' gestation and up to 42 days after a first delivery. Main Outcomes and Measures: The main outcome was a hospitalization or ED visit for a mental health condition, including mood and anxiety disorders, substance use, schizophrenia, and other psychotic disorder, or suicidality or self-harm event, arising at least 43 days after the first birth hospitalization. Cox regression models generated hazard ratios with 95% CIs, adjusted for baseline maternal comorbidities, maternal age at delivery, income quintile, type of residence, hospital type, and delivery year. Results: Of 2 026 594 individuals with a first hospital delivery, 1 579 392 individuals (mean [SD] age, 30.0 [5.4] years) had complete ED and hospital records and were included in analyses; among these, 35 825 individuals (2.3%) had SMM. Compared with individuals without SMM, those with SMM were older (mean [SD] age, 29.9 [5.4] years vs 30.7 [6.0] years), were more likely to deliver in a teaching tertiary care hospital (40.8% vs 51.1%), and to have preexisting conditions (eg, ≥2 conditions: 1.2% vs 5.3%), gestational diabetes (8.2% vs 11.7%), stillbirth (0.5% vs 1.6%), preterm birth (7.7% vs 25.0%), or cesarean delivery (31.0% vs 54.3%). After a median (IQR) duration of 2.6 (1.3-6.4) years, 1287 (96.1 per 10 000) individuals with SMM had a mental health hospitalization or ED visit, compared with 41 779 (73.2 per 10 000) individuals without SMM (adjusted hazard ratio, 1.26 [95% CI, 1.19-1.34]). Conclusions and Relevance: In this cohort study of postpartum individuals with and without SMM in pregnancy and delivery, there was an increased risk of mental health hospitalizations or ED visits up to 13 years after a delivery complicated by SMM. Enhanced surveillance and provision of postpartum mental health resources may be especially important after SMM.

Maternal mortality in the United States: are the high and rising rates due to changes in obstetrical factors, maternal medical conditions, or maternal mortality surveillance?

BACKGROUND: National Vital Statistics System reports show that maternal mortality rates in the United States have nearly doubled, from 17.4 in 2018 to 32.9 per 100,000 live births in 2021. However, these high and rising rates could reflect issues unrelated to obstetrical factors, such as changes in maternal medical conditions or maternal mortality surveillance (eg, due to introduction of the pregnancy checkbox). OBJECTIVE: This study aimed to assess if the high and rising rates of maternal mortality in the United States reflect changes in obstetrical factors, maternal medical conditions, or maternal mortality surveillance. STUDY DESIGN: The study was based on all deaths in the United States from 1999 to 2021. Maternal deaths were identified using the following 2 approaches: (1) per National Vital Statistics System methodology, as deaths in pregnancy or in the postpartum period, including deaths identified solely because of a positive pregnancy checkbox, and (2) under an alternative formulation, as deaths in pregnancy or in the postpartum period, with at least 1 mention of pregnancy among the multiple causes of death on the death certificate. The frequencies of major cause-of-death categories among deaths of female patients aged 15 to 44 years, maternal deaths, deaths due to obstetrical causes (ie, direct obstetrical deaths), and deaths due to maternal medical conditions aggravated by pregnancy or its management (ie, indirect obstetrical deaths) were quantified. RESULTS: Maternal deaths, per National Vital Statistics System methodology, increased by 144% (95% confidence interval, 130-159) from 9.65 in 1999-2002 (n=1550) to 23.6 per 100,000 live births in 2018-2021 (n=3489), with increases occurring among all race and ethnicity groups. Direct obstetrical deaths increased from 8.41 in 1999-2002 to 14.1 per 100,000 live births in 2018-2021, whereas indirect obstetrical deaths increased from 1.24 to 9.41 per 100,000 live births: 38% of direct obstetrical deaths and 87% of indirect obstetrical deaths in 2018-2021 were identified because of a positive pregnancy checkbox. The pregnancy checkbox was associated with increases in less specific and incidental causes of death. For example, maternal deaths with malignant neoplasms listed as a multiple cause of death increased 46-fold from 0.03 in 1999-2002 to 1.42 per 100,000 live births in 2018-2021. Under the alternative formulation, the maternal mortality rate was 10.2 in 1999-2002 and 10.4 per 100,000 live births in 2018-2021; deaths from direct obstetrical causes decreased from 7.05 to 5.82 per 100,000 live births. Deaths due to preeclampsia, eclampsia, postpartum hemorrhage, puerperal sepsis, venous complications, and embolism decreased, whereas deaths due to adherent placenta, renal and unspecified causes, cardiomyopathy, and preexisting hypertension increased. Maternal mortality increased among non-Hispanic White women and decreased among non-Hispanic Black and Hispanic women. However, rates were disproportionately higher among non-Hispanic Black women, with large disparities evident in several causes of death (eg, cardiomyopathy). CONCLUSION: The high and rising rates of maternal mortality in the United States are a consequence of changes in maternal mortality surveillance, with reliance on the pregnancy checkbox leading to an increase in misclassified maternal deaths. Identifying maternal deaths by requiring mention of pregnancy among the multiple causes of death shows lower, stable maternal mortality rates and declines in maternal deaths from direct obstetrical causes.

Prepregnancy body mass index and other risk factors for early-onset and late-onset haemolysis, elevated liver enzymes and low platelets (HELLP) syndrome: a population-based retrospective cohort study in British Columbia, Canada.

BACKGROUND: Obesity increases risk of pre-eclampsia, but the association with haemolysis, elevated liver enzymes and low platelets (HELLP) syndrome is understudied. OBJECTIVE: To examine the association between prepregnancy body mass index (BMI) and HELLP syndrome, including early-onset versus late-onset disease. STUDY DESIGN: A retrospective cohort study using population-based data. SETTING: British Columbia, Canada, 2008/2009-2019/2020. POPULATION: All pregnancies resulting in live births or stillbirths at ≥20 weeks' gestation. METHODS: BMI categories (kg/m2) included underweight (<18.5), normal (18.5-24.9), overweight (25.0-29.9) and obese (≥30.0). Rates of early-onset and late-onset HELLP syndrome (<34 vs ≥34 weeks, respectively) were calculated per 1000 ongoing pregnancies at 20 and 34 weeks' gestation, respectively. Cox regression was used to assess the associations between risk factors (eg, BMI, maternal age and parity) and early-onset versus late-onset HELLP syndrome. MAIN OUTCOME MEASURES: Early-onset and late-onset HELLP syndrome. RESULTS: The rates of HELLP syndrome per 1000 women were 2.8 overall (1116 cases among 391 941 women), and 1.9, 2.5, 3.2 and 4.0 in underweight, normal BMI, overweight and obese categories, respectively. Overall, gestational age-specific rates of HELLP syndrome increased with prepregnancy BMI. Obesity (compared with normal BMI) was more strongly associated with early-onset HELLP syndrome (adjusted HR (AHR) 2.24 (95% CI 1.65 to 3.04) than with late-onset HELLP syndrome (AHR 1.48, 95% CI 1.23 to 1.80) (p value for interaction 0.025). Chronic hypertension, multiple gestation, bleeding (<20 weeks' gestation and antepartum) also showed differing AHRs between early-onset versus late-onset HELLP syndrome. CONCLUSIONS: Prepregnancy BMI is positively associated with HELLP syndrome and the association is stronger with early-onset HELLP syndrome. Associations with early-onset and late-onset HELLP syndrome differed for some risk factors, suggesting possible differences in aetiological mechanisms.

COVID-19 Pandemic-Related Changes in Rates of Neonatal Abstinence Syndrome.

This cross-sectional study examines COVID-19 pandemic­related changes in rates of neonatal abstinence syndrome (NAS) and whether infants in urban or rural areas and those with low socioeconomic status were disproportionately affected.

Outcomes After Surgery at an Interdisciplinary Centre of Expertise for Endometriosis and Pelvic Pain in Canada: A Prospective Cohort Study.

OBJECTIVES: To prospectively evaluate pain-related quality-of-life (Endometriosis Health Profile-30 [EHP-30] pain subscale) after surgery at an interdisciplinary centre of expertise for endometriosis and pelvic pain. METHODS: A prospective cohort study was completed of persons undergoing surgical management for pelvic pain between December 2013 and July 2016 at an interdisciplinary tertiary referral centre for pelvic pain and endometriosis. We compared the change in EHP-30 scores for the following scenarios: (1) type of surgery (conservative surgery vs. hysterectomy), (2) stage of endometriosis (stage I/II vs. III/IV), and (3) age (age <40 vs. age ≥40 years). We used mixed-effects models to evaluate changes in pain during follow-up after surgery. RESULTS: Overall, 595 individuals met our inclusion criteria; the follow-up rate was 65.9% (392/595). In total, 436 (73.3%) underwent conservative surgery, while 159 (26.7%) underwent hysterectomy. Improvements in pain-related quality-of-life were seen for both conservative surgery and hysterectomy but greater improvements were seen with hysterectomy (P < 0.001). For conservative surgery, similar improvements in quality-of-life were observed regardless of endometriosis stage (I/II vs. III/IV) (P = 0.84) or age (<40 or ≥40 years old) (P = 0.87). We also observed similar improvements in quality-of-life regardless of stage (P = 0.24) or age (P = 0.71) after hysterectomy. CONCLUSIONS: At an interdisciplinary centre of expertise, there were significant improvements in quality-of-life after endometriosis surgery. These improvements were seen for both conservative surgery and hysterectomy (although greater improvement with the latter), for early and advanced stage disease, and younger and older patients.

A history of recurrent pregnancy loss is associated with increased perinatal complications, but not necessarily a longer birth interval: a population study spanning 18 years.

STUDY QUESTION: Is there a difference in the time interval between the first and second live births among individuals with and without recurrent pregnancy loss (RPL)? SUMMARY ANSWER: Primary RPL (two or more pregnancy losses before the first live birth) is associated with a shorter time interval between the first and second live births compared with individuals without RPL, but this association is reversed in patients with secondary RPL (RPL patients with no or one pregnancy loss before the first live birth). WHAT IS KNOWN ALREADY: There is limited information regarding the ability to have more than one child for patients with RPL. Previous studies have investigated the time to live birth and the live birth rate from the initial presentation to clinical providers. Most of the previous studies have included only patients treated at specialized RPL clinics and thus may be limited by selection bias, including patients with a more severe condition. STUDY DESIGN, SIZE, DURATION: We conducted a population-based retrospective cohort study of 184 241 participants who delivered in British Columbia, Canada, and had at least two recorded live births between 2000 and 2018. The aim was to study the differences in the time interval between the first and second live births and the prevalence of pregnancy complications in patients with and without RPL. Additionally, 198 319 individuals with their first live birth between 2000 and 2010 were studied to evaluate cumulative second live birth rates. PARTICIPANTS/MATERIALS, SETTING, METHODS: Among individuals with at least two recorded live births between 2000 and 2018, 12 321 patients with RPL and 171 920 participants without RPL were included. RPL was defined as at least two pregnancy losses before 20 weeks gestation. Patients with primary RPL had at least two pregnancy losses occurring before the first live birth, while patients with secondary RPL had no or one pregnancy loss before the first live birth. We compared the time interval from the first to second live birth in patients with primary RPL, those with secondary RPL, and participants without RPL using generalized additive models to allow for a non-linear relationship between maternal age and time interval between first and second live births. We also compared prevalence of pregnancy complications at the first and second live births between the groups using non-parametric Kruskal-Wallis H test and Fisher's exact test for continuous and categorical variables, respectively. We assessed the cumulative second live birth rates in patients with primary RPL and those without RPL, among participants who had their first live birth between 2000 and 2010. Cox proportional hazards model was used to estimate and compare hazard ratios between the two groups using a stratified modelling approach. MAIN RESULTS AND THE ROLE OF CHANCE: The adjusted time interval between the first and second live births was the longest in patients with secondary RPL, followed by individuals without RPL, and the shortest time interval was observed in patients with primary RPL: 4.34 years (95% CI: 4.09-4.58), 3.20 years (95% CI: 3.00-3.40), and 3.05 years (95% CI: 2.79-3.32). A higher frequency of pregnancy losses was associated with an increased time interval between the first and second live births. The prevalence of pregnancy complications at the first and second live births, including gestational diabetes, hypertensive disorder of pregnancy, preterm birth, and multiple gestations was significantly higher in patients with primary RPL compared with those without RPL. The cumulative second live birth rate was significantly lower in patients with primary RPL compared with individuals without RPL. LIMITATIONS, REASONS FOR CAUTION: This study may be limited by its retrospective nature. Although we adjusted for multiple potential confounders, there may be residual confounding due to a lack of information about pregnancy intentions and other factors, including unreported pregnancy losses. WIDER IMPLICATIONS OF THE FINDINGS: The results of this study provide information that will help clinicians in the counselling of RPL patients who desire a second child. STUDY FUNDING/COMPETING INTEREST(S): This study was supported in part by a grant from the Canadian Institutes of Health Research (CIHR): Reference Number W11-179912. M.A.B. reports research grants from CIHR and Ferring Pharmaceutical. He is also on the advisory board for AbbVie, Pfizer, and Baxter. The other authors report no conflict of interest. TRIAL REGISTRATION NUMBER: NCT04360564.

Variation in Episiotomy Use Among Nulliparous Individuals by Maternity Care Provider and Associated Rates of Obstetric Anal Sphincter Injury.

OBJECTIVES: To quantify variation in the association between episiotomy and obstetric anal sphincter injury (OASI) by maternity care provider in spontaneous and operative vaginal deliveries (SVDs and OVDs). METHODS: Population-based retrospective cohort study of vaginal, term deliveries among nullipara in Canada (2004-2015). Adjusted rate ratios (ARRs) and 95% CIs were estimated using log-binomial regression to quantify the associations between episiotomy and OASI, stratified by care provider (obstetrician [OB], family physician [FP], or registered midwife [RM]) while adjusting for potential confounders. RESULTS: The study included 631 642 deliveries. Episiotomy use varied by provider: among SVDs, the episiotomy rate was 19.6%, 14.4%, and 8.4% in the OB, FP, and RM groups, respectively. The rate of OASI was higher among SVDs with versus without episiotomy (5.8% vs 4.6%). Conversely, OASI occurred less frequently in operative vaginal deliveries with episiotomy (15.3%) compared with those without (16.7%). In all provider groups, the ARR for OASI was increased with episiotomy in SVD and decreased with episiotomy with forceps delivery. No differences in these associations were observed by provider except among vacuum delivery (ARR with episiotomy vs. without, OB: 0.88, 95% CI 0.84-0.92; FP: 0.89, 95% CI 0.83-0.96, RM: 1.22, 95% CI 1.02-1.48). CONCLUSIONS: In nullipara, irrespective of maternity care provider, there is a positive association between episiotomy and OASI among SVDs and an inverse association between episiotomy and deliveries with forceps. The relationship between episiotomy and OASI is modified by maternity care providers among vacuum deliveries.

Temporal changes in pre-existing health conditions five years prior to pregnancy in British Columbia, Canada, 2000-2019.

BACKGROUND: Pre-existing health conditions increase the risk of obstetric complications during pregnancy and birth. However, the prevalence and recent changes in the frequency of pre-existing health conditions in the childbearing population remain unknown. OBJECTIVES: To estimate the temporal changes in the prevalence of pre-existing health conditions among pregnant women in British Columbia, Canada. METHODS: We carried out a population-based cross-sectional study of 825,203 deliveries in BC between 2000 and 2019 and examined 17 categories of physical and psychiatric health conditions recorded within 5 years before childbirth. We also undertook age-period-cohort analyses to evaluate temporal changes in pre-existing health conditions. RESULTS: The prevalence of any pre-existing health condition was 26.2% (n = 216,214) with overall trends remaining stable during the study period. Between 2000 and 2019, the prevalence rates of anxiety (5.6%-9.6%), bipolar (1.6%-3.4%), psychosis (0.7%-0.8%), and eating disorders (0.2%-0.3%) increased. The prevalence of hypertension increased sharply from 0.06% in 2000 to 0.3% in 2019. Diabetes mellitus and stroke rates increased, as did the prevalence of systemic lupus, multiple sclerosis, and chronic kidney disease. Advanced maternal age was strongly associated with both psychiatric and circulatory/metabolic conditions. A strong birth cohort effect was evident, with rates of psychiatric conditions increasing among women born after 1985. CONCLUSIONS: In British Columbia, Canada, 1 in 4 mothers had a pre-existing health condition 5 years prior to pregnancy. These findings underscore the need for multi-disciplinary care for women with pre-existing health conditions to improve maternal, foetal, and infant health.

Obesity, Twin Pregnancy, and the Role of Assisted Reproductive Technology.

Importance: The prevalence of overweight and obesity (body mass index [BMI] ≥25) has increased globally, and high BMI has been linked to higher rates of twin birth. However, evidence from large population-based studies is lacking; the issue needs careful study, as women with obesity are also more likely to use assisted reproductive technology (ART), which frequently results in twin pregnancy. Objective: To examine the association between BMI and twin birth and the role of ART as a potential mediator in this association. Design, Setting, and Participants: This retrospective cohort study included all live births and stillbirths with gestational age of 20 weeks or longer in British Columbia, Canada, from 2008 to 2020, using data from the British Columbia Perinatal Database Registry. Data analysis was conducted from November 2022 to June 2023. Exposures: Prepregnancy BMI, calculated as weight in kilograms divided by height in meters squared, and use of ART. Main Outcomes and Measures: The study assessed whether prepregnancy BMI is associated with the rate of twin vs singleton delivery and whether this association is explained by the differential use of ART in women with obesity. Results: A total of 524 845 deliveries at 20 weeks' or longer gestation occurred in British Columbia during the study period, and 392 046 women had complete data on prepregnancy BMI. The median (IQR) age was 31.4 (27.7-35.0) years, approximately half were nulliparous (243 443 [46.4%]) and less than 10% smoked during pregnancy (36 894 [7.1%]). Overall, 8295 women had a twin delivery (15.8 per 1000 deliveries), and rates per 1000 deliveries by prepregnancy BMI categories were 11.9 (underweight), 15.1 (normal), 16.0 (overweight), 16.0 (obesity class I), 16.7 (obesity class II), and 18.9 (obesity class III). After adjustment for other covariates, women with underweight had relatively 16% fewer twins compared with women with normal BMI (adjusted risk ratio [aRR], 0.84; 95% CI, 0.74-0.95), while women with overweight, class I obesity, class II obesity, and class III obesity had 14% (aRR, 1.14; 95% CI, 1.07-1.21), 16% (aRR, 1.16; 95% CI, 1.06-1.27), 17% (aRR, 1.17; 95% CI, 1.02-1.34), and 41% higher rates (aRR, 1.41; 95% CI, 1.19-1.66), respectively. The proportion of women who conceived by ART increased with increasing BMI, and ART was associated with nearly a 12-fold higher rate of twin delivery (aRR, 11.80; 95% CI 11.10-12.54). ART explained about a quarter of the association between obesity class I and II and twin delivery (eg, obesity class I, 23% mediated; 95% CI, 7%-39% mediated), but none of this association was mediated by ART in women with class III obesity. Conclusions and relevance: In this cohort study of 524 845 births, the rate of twin birth increased with increasing prepregnancy BMI. In women with a BMI between 30 and 40, approximately one-quarter of this association was explained by higher use of ART; however, there was no evidence of such mediation in women with BMI of 40 or greater.

Effect of the COVID-19 Pandemic on Stillbirths in Canada and the United States.

OBJECTIVE: There is uncertainty regarding the effect of the COVID-19 pandemic on population rates of stillbirth. We quantified pandemic-associated changes in stillbirth rates in Canada and the United States. METHODS: We carried out a retrospective study that included all live births and stillbirths in Canada and the United States from 2015 to 2020. The primary analysis was based on all stillbirths and live births at ≥20 weeks gestation. Stillbirth rates were analyzed by month, with March 2020 considered to be the month of pandemic onset. Interrupted time series analyses were used to determine pandemic effects. RESULTS: The study population included 18 475 stillbirths and 2 244 240 live births in Canada and 134 883 stillbirths and 22 963 356 live births in the United States (8.2 and 5.8 stillbirths per 1000 total births, respectively). In Canada, pandemic onset was associated with an increase in stillbirths at ≥20 weeks gestation of 1.01 (95% confidence interval [CI] 0.56-1.46) per 1000 total births and an increase in stillbirths at ≥28 weeks gestation of 0.35 (95% CI 0.16-0.54) per 1000 total births. In the United States, pandemic onset was associated with an increase in stillbirths at ≥20 weeks gestation of 0.48 (95% CI 0.22-0.75) per 1000 total births and an increase in stillbirths at ≥28 weeks gestation of 0.22 (95% CI 0.12-0.32) per 1000 total births. The increase in stillbirths at pandemic onset returned to pre-pandemic levels in subsequent months. CONCLUSION: The COVID-19 pandemic's onset was associated with a transitory increase in stillbirth rates in Canada and the United States.

Feasibility and acceptability of collecting umbilical cord tissue for prenatal cannabis research: A mixed-methods research study.

BACKGROUND: Large-scale longitudinal studies with biological samples are needed to examine the associations between prenatal cannabis use and birth and developmental outcomes. OBJECTIVES: The aim of this study was to understand the feasibility and acceptability of collecting umbilical cord tissue for the purpose of cannabis use testing in a community sample. DESIGN: This is a mixed methods research study consisted of a prospective cohort study and a qualitative descriptive study. METHODS: This study was conducted in Vancouver, British Columbia between January 2021 and August 2022. Participants were recruited during pregnancy, and the umbilical cord tissues were collected at birth and tested for the presence of cannabinoids. After the completion of the study, participants completed an online open-ended questionnaire about their overall experience. Data were analyzed using descriptive and thematic analyses. RESULTS: Among the 85 eligible individuals, 57 people (67%) consented to the study. The cord tissue was collected for 39 participants (68.4%). The collection rates for participants with vaginal, elective, and emergency cesarean delivery were 73.0%, 71.4%, and 53.8%, respectively, and for those with spontaneous and induced labor were 81.5% and 50%, respectively. Four (7.0%) and seven participants (12.3%) reported prenatal cannabis use in direct and probing self-report questions, respectively. The agreement between any self-report and cord tissue test was moderate (kappa 0.53, 95% confidence interval 0.06-0.99). Qualitative findings were classified into five themes. CONCLUSION: The collection of cord tissue was perceived acceptable by most participants. Implementation of collection protocols for complex labors, a central hospital unit to liaise direct communications and active participants' involvement might increase the feasibility of future studies.

Neonatal mortality risk of large-for-gestational-age and macrosomic live births in 15 countries, including 115.6 million nationwide linked records, 2000-2020.

OBJECTIVE: We aimed to compare the prevalence and neonatal mortality associated with large for gestational age (LGA) and macrosomia among 115.6 million live births in 15 countries, between 2000 and 2020. DESIGN: Population-based, multi-country study. SETTING: National healthcare systems. POPULATION: Liveborn infants. METHODS: We used individual-level data identified for the Vulnerable Newborn Measurement Collaboration. We calculated the prevalence and relative risk (RR) of neonatal mortality among live births born at term + LGA (>90th centile, and also >95th and >97th centiles when the data were available) versus term + appropriate for gestational age (AGA, 10th-90th centiles) and macrosomic (≥4000, ≥4500 and ≥5000 g, regardless of gestational age) versus 2500-3999 g. INTERGROWTH 21st served as the reference population. MAIN OUTCOME MEASURES: Prevalence and neonatal mortality risks. RESULTS: Large for gestational age was common (median prevalence 18.2%; interquartile range, IQR, 13.5%-22.0%), and overall was associated with a lower neonatal mortality risk compared with AGA (RR 0.83, 95% CI 0.77-0.89). Around one in ten babies were ≥4000 g (median prevalence 9.6% (IQR 6.4%-13.3%), with 1.2% (IQR 0.7%-2.0%) ≥4500 g and with 0.2% (IQR 0.1%-0.2%) ≥5000 g). Overall, macrosomia of ≥4000 g was not associated with increased neonatal mortality risk (RR 0.80, 95% CI 0.69-0.94); however, a higher risk was observed for birthweights of ≥4500 g (RR 1.52, 95% CI 1.10-2.11) and ≥5000 g (RR 4.54, 95% CI 2.58-7.99), compared with birthweights of 2500-3999 g, with the highest risk observed in the first 7 days of life. CONCLUSIONS: In this population, birthweight of ≥4500 g was the most useful marker for early mortality risk in big babies and could be used to guide clinical management decisions.

Stillbirths: Contribution of preterm birth and size-for-gestational age for 125.4 million total births from nationwide records in 13 countries, 2000-2020.

OBJECTIVE: To examine the contribution of preterm birth and size-for-gestational age in stillbirths using six 'newborn types'. DESIGN: Population-based multi-country analyses. SETTING: Births collected through routine data systems in 13 countries. SAMPLE: 125 419 255 total births from 22+0 to 44+6 weeks' gestation identified from 2000 to 2020. METHODS: We included 635 107 stillbirths from 22+0 weeks' gestation from 13 countries. We classified all births, including stillbirths, into six 'newborn types' based on gestational age information (preterm, PT, <37+0 weeks versus term, T, ≥37+0 weeks) and size-for-gestational age defined as small (SGA, <10th centile), appropriate (AGA, 10th-90th centiles) or large (LGA, >90th centile) for gestational age, according to the international newborn size for gestational age and sex INTERGROWTH-21st standards. MAIN OUTCOME MEASURES: Distribution of stillbirths, stillbirth rates and rate ratios according to six newborn types. RESULTS: 635 107 (0.5%) of the 125 419 255 total births resulted in stillbirth after 22+0 weeks. Most stillbirths (74.3%) were preterm. Around 21.2% were SGA types (PT + SGA [16.2%], PT + AGA [48.3%], T + SGA [5.0%]) and 14.1% were LGA types (PT + LGA [9.9%], T + LGA [4.2%]). The median rate ratio (RR) for stillbirth was highest in PT + SGA babies (RR 81.1, interquartile range [IQR], 68.8-118.8) followed by PT + AGA (RR 25.0, IQR, 20.0-34.3), PT + LGA (RR 25.9, IQR, 13.8-28.7) and T + SGA (RR 5.6, IQR, 5.1-6.0) compared with T + AGA. Stillbirth rate ratios were similar for T + LGA versus T + AGA (RR 0.7, IQR, 0.7-1.1). At the population level, 25% of stillbirths were attributable to small-for-gestational-age. CONCLUSIONS: In these high-quality data from high/middle income countries, almost three-quarters of stillbirths were born preterm and a fifth small-for-gestational age, with the highest stillbirth rates associated with the coexistence of preterm and SGA. Further analyses are needed to better understand patterns of gestation-specific risk in these populations, as well as patterns in lower-income contexts, especially those with higher rates of intrapartum stillbirth and SGA.

Maternal and perinatal outcomes in primiparous singleton pregnancies conceived with assisted reproductive technology in British Columbia.

OBJECTIVE: To evaluate the odds of developing adverse maternal and perinatal outcomes in primiparous singleton pregnancies conceived with assisted reproductive technology (ART) compared with pregnancies conceived without ART. STUDY DESIGN: A retrospective population-based cohort study using data from the British Columbia Perinatal Data Registry. The population included primiparous women with singleton live or stillbirths delivering at or after 20 weeks' gestation between April 1st 2008-March 31st, 2021. Women who conceived with ART were compared with those who conceived without ART. The main outcome measures were gestational diabetes, hypertensive disorders of pregnancy, preterm birth, low birth weight, neonatal intensive care unit admission, stillbirth, and 5-minute Apgar score. Adjusted odds ratios were calculated. RESULTS: The study population included 191,059 primiparous women: 183,819 conceived without ART, 7,240 conceived using ART. After controlling for age, body mass index, pre-gestational diabetes, and smoking status, singleton pregnancies conceived by ART had significantly higher odds of gestational diabetes (OR 1.18, 95 % confidence interval [CI] 1.10-1.26) and hypertensive disorders of pregnancy (OR 1.39, 95 % CI 1.29-1.51). There were also significantly increased odds of preterm birth (OR 1.35, 95 % CI 1.25-1.46), low birth weight (OR 1.35, 95 % CI 1.23-1.49), and neonatal intensive care unit admission (OR 1.21, 95 % CI 1.11-1.32). There was not a statistically significant difference in the odds of stillbirth (OR 1.06, 95 % CI 0.72-1.57) or 5-minute Apgar score < 7 (OR 1.10, 95 % CI 0.97-1.26). CONCLUSION: There is an increased odds of developing several adverse maternal or neonatal outcomes in primiparous singleton pregnancies conceived by ART including gestational diabetes, hypertensive disorders of pregnancy, preterm birth, low birth weight, and increased incidence of neonatal intensive care unit admissions.

Obstetric Intervention and Perinatal Outcomes During the Coronavirus Disease 2019 (COVID-19) Pandemic.

OBJECTIVE: To quantify pandemic-related changes in obstetric intervention and perinatal outcomes in the United States. METHODS: We carried out a retrospective study of all live births and fetal deaths in the United States, 2015-2021, with data obtained from the natality, fetal death, and linked live birth-infant death files of the National Center for Health Statistics. Analyses were carried out among all singletons; singletons of patients with prepregnancy diabetes, prepregnancy hypertension, and hypertensive disorders of pregnancy; and twins. Outcomes of interest included preterm birth, preterm labor induction or preterm cesarean delivery, macrosomia, postterm birth, and perinatal death. Interrupted time series analyses were used to estimate changes in the prepandemic period (January 2015-February 2020), at pandemic onset (March 2020), and in the pandemic period (March 2020-December 2021). RESULTS: The study population included 26,604,392 live births and 155,214 stillbirths. The prepandemic period was characterized by temporal increases in preterm birth and preterm labor induction or cesarean delivery rates and temporal reductions in macrosomia, postterm birth, and perinatal mortality. Pandemic onset was associated with absolute decreases in preterm birth (decrease of 0.322/100 live births, 95% CI 0.506-0.139) and preterm labor induction or cesarean delivery (decrease of 0.190/100 live births, 95% CI 0.334-0.047) and absolute increases in macrosomia (increase of 0.046/100 live births), postterm birth (increase of 0.015/100 live births), and perinatal death (increase of 0.501/1,000 total births, 95% CI 0.220-0.783). These changes were larger in subpopulations at high risk (eg, among singletons of patients with prepregnancy diabetes). Among singletons of patients with prepregnancy diabetes, pandemic onset was associated with a decrease in preterm birth (decrease of 1.634/100 live births) and preterm labor induction or cesarean delivery (decrease of 1.521/100 live births) and increases in macrosomia (increase of 0.328/100 live births) and perinatal death (increase of 9.840/1,000 total births, 95% CI 3.933-15.75). Most changes were reversed in the months after pandemic onset. CONCLUSION: The onset of the coronavirus disease 2019 (COVID-19) pandemic was associated with a transient decrease in obstetric intervention (especially preterm labor induction or cesarean delivery) and a transient increase in perinatal mortality.

Pre-pregnancy and pregnancy disorders, pre-term birth and the risk of cerebral palsy: a population-based study.

BACKGROUND: Cerebral palsy (CP) is the most common cause of childhood physical disability whose aetiology remains unclear in most cases. Maternal pre-existing and pregnancy complications are recognized risk factors of CP but the extent to which their effects are mediated by pre-term birth is unknown. METHODS: Population-based cohort study in Sweden including 2 055 378 singleton infants without congenital abnormalities, born between 1999 and 2019. Data on maternal and pregnancy characteristics and diagnoses of CP were obtained by individual record linkages of nationwide Swedish registries. Exposure was defined as maternal pre-pregnancy and pregnancy disorders. Inpatient and outpatient diagnoses were obtained for CP after 27 days of age. Adjusted rate ratios (aRRs) were calculated, along with 95% CIs. RESULTS: A total of 515 771 (25%) offspring were exposed to maternal pre-existing chronic disorders and 3472 children with CP were identified for a cumulative incidence of 1.7 per 1000 live births. After adjusting for potential confounders, maternal chronic cardiovascular or metabolic disorders, other chronic diseases, mental health disorders and early-pregnancy obesity were associated with 1.89-, 1.24-, 1.26- and 1.35-times higher risk (aRRs) of CP, respectively. Most notably, offspring exposed to maternal antepartum haemorrhage had a 6-fold elevated risk of CP (aRR 5.78, 95% CI, 5.00-6.68). Mediation analysis revealed that ∼50% of the effect of these associations was mediated by pre-term delivery; however, increased risks were also observed among term infants. CONCLUSIONS: Exposure to pre-existing maternal chronic disorders and pregnancy-related complications increases the risk of CP in offspring. Although most infants with CP were born at term, pre-term delivery explained 50% of the overall effect of pre-pregnancy and pregnancy disorders on CP.