Risk of birth defects in children of mothers with defects.

BACKGROUND: There is evidence that women with congenital anomalies are at risk of having an infant with the same defect. However, the risk of having an infant with a different type of defect is less well described. AIMS: We evaluated the extent to which offspring of women with congenital anomalies were at risk of having a birth defect, including defects that were similar to or different from their mother's. METHODS: We analyzed a retrospective cohort of 1,311,532 infants born in Canada between 2006 and 2022. The exposure was a maternal congenital anomaly, and the outcome included birth defects in the newborn. We estimated risk ratios (RR) and confidence intervals (CI) for the association of specific maternal anomalies with the risk of having an infant with a similar or different defect using log-binomial regression models adjusted for patient characteristics. RESULTS: While mothers with anomalies were at risk of having an infant with the same defect, associations with other types of defects were not as strong. For example, compared with no maternal anomaly, maternal urogenital defects were associated with up to 45 times the risk of having an infant with a similar urogenital defect (RR 45.33, 95 % CI 31.92-64.36), but <2 times the risk of having an infant with orofacial clefts (RR 1.89, 95 % CI 1.07-3.34) and clubfoot (RR 1.36, 95 % CI 1.02-1.81). CONCLUSION: The findings suggest that maternal congenital anomalies are only weakly associated with occurrence of a different type of defect in offspring.

Underlying Causes of Ethnocultural Inequality in Pregnancy Outcomes: Role of Hospital Proximity.

We evaluated the contribution of place of birth to ethnocultural inequality in pregnancy outcomes. We analyzed a cohort of 1,487,723 births between 1998 and 2019 among minority Anglophones and majority Francophones in Quebec, Canada. We estimated the association (adjusted risk ratio, RR; 95% confidence interval, CI) of language with preterm birth and stillbirth, and incorporated interaction terms to determine the contribution of place of birth and distance traveled. Compared with Francophones, minority Anglophones had a greater risk of preterm birth (RR 1.03; 95% CI 1.01-1.06) and were less likely to deliver farther from home (RR 0.95; 95% CI 0.94-0.95). Anglophones who delivered close to home had a higher risk of preterm birth (RR 1.07; 95% CI 1.04-1.11), whereas Anglophones who delivered farther had a lower risk (RR 0.69; 95% CI 0.64-0.75). Patterns were similar for stillbirth. Ethnocultural inequality in adverse birth outcomes may be influenced by place of birth.

Social Media and Selfie-Related Mortality Amid COVID-19: Interrupted Time Series Analysis.

BACKGROUND: COVID-19 had a considerable impact on mortality, but its effect on behaviors associated with social media remains unclear. As travel decreased due to lockdowns during the pandemic, selfie-related mortality may have decreased, as fewer individuals were taking smartphone photographs in risky locations. OBJECTIVE: In this study, we examined the effect of the COVID-19 pandemic on trends in selfie-related mortality. METHODS: We identified fatal selfie-related injuries reported in web-based news reports worldwide between March 2014 and April 2021, including the deaths of individuals attempting a selfie photograph or anyone else present during the incident. The main outcome measure was the total number of selfie-related deaths per month. We used interrupted time series regression to estimate the monthly change in the number of selfie-related deaths over time, comparing the period before the pandemic (March 2014 to February 2020) with the period during the pandemic (March 2020 to April 2021). RESULTS: The study included a total of 332 selfie-related deaths occurring between March 2014 and April 2021, with 18 (5.4%) deaths during the pandemic. Most selfie-related deaths occurred in India (n=153, 46.1%) and involved men (n=221, 66.6%) and young individuals (n=296, 89.2%). During the pandemic, two-thirds of selfie-related deaths were due to falls, whereas a greater proportion of selfie-related deaths before the pandemic were due to drowning. Based on interrupted time series regression, there was an average of 1.3 selfie-related deaths per month during the pandemic, compared with 4.3 deaths per month before the pandemic. The number of selfie-related deaths decreased by 2.6 in the first month of the pandemic alone and continued to decrease thereafter. CONCLUSIONS: Our findings indicate that the COVID-19 pandemic led to a marked decrease in selfie-related mortality, suggesting that lockdowns and travel restrictions likely prevented hazardous selfie-taking. The decrease in selfie-related mortality occurred despite a potential increase in social media use during the pandemic.

Association between First Trimester Exposure to Ambient PM2.5 and NO2 and Congenital Heart Defects: A Population-Based Cohort Study of 1,342,198 Live Births in Canada.

BACKGROUND: The extent to which ambient air pollution contributes to the pathogenesis of congenital heart defects remains uncertain. OBJECTIVE: We investigated whether first trimester exposure to ambient fine particulate matter (PM2.5) and nitrogen dioxide (NO2) was associated with the risk of critical and noncritical heart defects in a large population-based cohort of births. METHODS: We carried out a retrospective cohort study of children conceived between 2000 and 2016 in Quebec, Canada. Heart defects were identified via data from the Maintenance and Use of Data for the Study of Hospital Clientele registry. The main exposures were average concentration of PM2.5 and NO2 in a) the first trimester and b) the month of conception. Exposures were estimated at the residential postal code. Associations with critical and noncritical heart defects were assessed using logistic regression models, adjusted for maternal and infant characteristics. We considered single- and two-pollutant models and assessed modifying effects of maternal comorbidity, including preexisting hypertension, preeclampsia, anemia, and diabetes. RESULTS: The cohort comprised 1,342,198 newborns, including 12,715 with heart defects. Exposure in the first trimester and month of conception yielded similar results; both were associated with a greater risk of heart defects. Adjusted odds ratios (OR) for any heart defect per interquartile range increase were 1.02 (95% CI: 1.00, 1.05) for PM2.5 and 1.10 (95% CI: 1.07, 1.13) for NO2. Associations with atrial septal defects were 1.08 (95% CI: 1.03, 1.14) for PM2.5 and 1.19 (95% CI: 1.12, 1.25) for NO2. Corresponding ORs for ventricular septal defects and individual critical heart defects were not significant. PM2.5 (OR=1.11; 95% CI: 1.06, 1.17) and NO2 (OR=1.23; 95% CI: 1.17, 1.31) exposure were associated with a greater risk of heart defects in mothers with comorbidity. DISCUSSION: In this population-based cohort, prenatal exposure to ambient air pollution during the first trimester was associated with an increased risk of heart defects, particularly atrial septal defects. The association with heart defects was greater in mothers with comorbidity. https://doi.org/10.1289/EHP11120.

Shifting age of child eating disorder hospitalizations during the Covid-19 pandemic.

BACKGROUND: We studied the effect of the Covid-19 pandemic on child eating disorder hospitalizations in Quebec, Canada. Quebec had one of the strictest lockdown measures targeting young people in North America. METHODS: We analyzed eating disorder hospitalizations in children aged 10-19 years before and during the pandemic. We used interrupted time series regression to assess trends in the monthly number of hospitalizations for anorexia nervosa, bulimia nervosa, and other eating disorders before the pandemic (April 2006 to February 2020), and during the first (March to August 2020) and second waves (September 2020 to March 2021). We determined the types of eating disorders requiring hospital treatment and identified the age, sex and socioeconomic subgroups that were most affected. RESULTS: Hospitalization rates for eating disorders increased during the first (6.5 per 10,000) and second waves (12.8 per 10,000) compared with the period before the pandemic (5.8 per 10,000). The increase occurred for anorexia nervosa as well as other types of eating disorders. The number of girls and boys aged 10-14 years admitted for eating disorders increased during wave 1. Wave 2 triggered an increase in eating disorder admissions among girls aged 15-19 years. Hospitalization rates increased earlier for advantaged than disadvantaged youth. CONCLUSIONS: The Covid-19 pandemic affected hospitalizations for anorexia nervosa as well as other eating disorders, beginning with girls aged 10-14 years during wave 1, followed by girls aged 15-19 years during wave 2. Boys aged 10-14 years were also affected, as well as both advantaged and disadvantaged youth.

Access to perinatal healthcare in minority Anglophones: Hospital type and birth outcomes.

OBJECTIVES: We assessed the relationship between hospital characteristics and risk of adverse birth outcomes among minority Anglophones in Montreal, Canada. METHODS: The study included 124,670 births among Anglophones in metropolitan Montreal between 1998 and 2019. We estimated risk ratios (RR) and 95% confidence intervals (CI) for the association between hospital characteristics, including residential proximity to hospitals and language in which medical services are provided, and risks of preterm birth and stillbirth. Models were adjusted for maternal socioeconomic status and other characteristics. RESULTS: In this study, 8% of Anglophones had a preterm birth and 0.4% a stillbirth. Anglophone women who delivered at a farther French hospital had a greater risk of stillbirth (RR 1.67, 95% CI 1.28-2.18) than preterm birth (RR 1.21, 95% CI 1.14-1.30), compared with delivery at hospitals closer to home. In contrast, delivery at a farther English hospital was associated with similar risks of stillbirth (RR 1.36, 95% CI 1.08-1.71) and preterm birth (RR 1.36, 95% CI 1.29-1.44). The greater risk of stillbirth with delivery at a farther French hospital, versus greater risk of preterm birth at a farther English hospital, remained present in analyses stratified by maternal age, education, material deprivation, and region of origin. CONCLUSION: Minority Anglophones in Montreal who travel to a farther French hospital for delivery have a greater risk of stillbirth than Anglophones who travel to a farther English hospital. This novel observation suggests the need to determine if access to perinatal healthcare in a woman's language may help reduce the risk of stillbirth.

Association of Maternal and Neonatal Birth Outcomes With Subsequent Pediatric Transplants.

BACKGROUND: We identified maternal and neonatal birth characteristics that were associated with organ or tissue transplants during childhood. METHODS: We designed a retrospective cohort study of the population of children born between 2006 and 2019 in Quebec, Canada. The exposure included birth complications such as congenital anomaly, neonatal blood transfusion, and oligohydramnios. The main outcome measure was organ or tissue transplantation before 14 y of age. We categorized transplants according to type (major organs versus superficial tissues). To determine the association of birth characteristics with risk of pediatric transplant, we estimated hazard ratios (HRs) and 95% confidence intervals (CIs) using Cox proportional hazards models adjusted for potential confounders. RESULTS: The cohort comprised 1 038 375 children with 7 712 678 person-years of follow-up, including 436 children who had transplants before 14 y of age. Birth complications were predominantly associated with major organ transplants. Congenital anomaly was associated with heart or lung (HR, 10.41; 95% CI, 5.33-20.33) and kidney transplants (HR, 13.69; 95% CI, 7.48-25.06), compared with no anomaly. Neonatal blood transfusion was associated with all major organ transplants, compared with no transfusion. Maternal complications were not as strongly associated with the risk of childhood transplant, although oligohydramnios was associated with 16.84 times (95% CI, 8.09-35.02) the risk of kidney transplant, compared with no oligohydramnios. CONCLUSIONS: Adverse birth outcomes such as congenital anomaly, neonatal blood transfusion, and maternal oligohydramnios are associated with a greater risk of transplantation before 14 y of age. Maternal and neonatal birth outcomes may be useful predictors of transplantation.

Extended Risk of Mortality in Children with Inborn Errors of Metabolism: A Longitudinal Cohort Study.

OBJECTIVES: To determine the long-term risk of mortality among children with inborn errors of metabolism. STUDY DESIGN: We conducted a retrospective cohort study of 1750 children with inborn errors of metabolism (excluding mitochondrial disorders) and 1 036 668 children without errors of metabolism who were born in Quebec, Canada, between 2006 and 2019. Main outcome measures included all-cause and cause-specific mortality between birth and 14 years of age. We used adjusted survival regression models to estimate HRs and 95% CIs for the association between inborn errors of metabolism and mortality over time. RESULTS: Mortality rates were greater for children with errors of metabolism than for unaffected children (69.1 vs 3.2 deaths per 10 000 person-years). During 7 702 179 person-years of follow-up, inborn errors of metabolism were associated with 21.2 times the risk of mortality compared with no error of metabolism (95% CI 17.23-26.11). Disorders of mineral metabolism were associated with greater mortality the first 28 days of life (HR 60.62, 95% CI 10.04-365.98), and disorders of sphingolipid metabolism were associated with greater mortality by 1 year (HR 284.73, 95% CI 139.20-582.44) and 14 years (HR 1066.00, 95% CI 298.91-3801.63). Errors of metabolism were disproportionately associated with death from hepatic/digestive (HR 208.21, 95% CI 90.28-480.22), respiratory (HR 116.57, 95% CI 71.06-191.23), and infectious causes (HR 119.83, 95% CI 40.56-354.04). CONCLUSIONS: Children with errors of metabolism have a considerably elevated risk of mortality before 14 years, including death from hepatic/digestive, respiratory, and infectious causes. Targeting these causes of death may help improve long-term survival.

Longitudinal risk of maternal hospitalization for mental illness following preterm birth.

BACKGROUND: Preterm birth may affect maternal mental health, yet most studies focus on postpartum mental disorders only. We explored the relationship between preterm delivery and the long-term risk of maternal hospitalization for mental illness after pregnancy. METHODS: We performed a longitudinal cohort study of 1,381,300 women who delivered between 1989 and 2021 in Quebec, Canada, and had no prior history of mental illness. The exposure was preterm birth, including extreme (<28 weeks), very (28-31 weeks), and moderate to late (32-36 weeks). The outcome was subsequent maternal hospitalization for depression, bipolar, psychotic, stress and anxiety, personality disorders, and self-harm up to 32 years later. We used adjusted Cox proportional hazards models to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association between preterm birth and mental illness hospitalization. RESULTS: Compared with term, women who delivered preterm had a higher rate of mental illness hospitalization (3.81 vs. 3.01 per 1000 person-years). Preterm birth was associated with any mental illness (HR 1.38, 95% CI 1.35-1.41), including depression (HR 1.37, 95% CI 1.32-1.41), psychotic disorders (HR 1.35, 95% CI 1.25-1.44), and stress and anxiety disorders (HR 1.42, 95% CI 1.38-1.46). Delivery at any preterm gestational age was associated with the risk of mental hospitalization, but risks were greatest around 34 weeks of gestation. Preterm birth was strongly associated with mental illness hospitalization within 2 years of pregnancy, although associations persisted throughout follow-up. CONCLUSIONS: Women who deliver preterm may be at risk of mental disorders in the short and long term.

Association of Endometriosis and Severe Maternal Morbidity.

OBJECTIVE: To evaluate the association between endometriosis and risk of severe maternal morbidity (SMM). METHODS: We conducted a population-based retrospective cohort study of 2,412,823 deliveries at hospitals in Quebec, Canada, between 1989 and 2019. The exposure was surgically confirmed endometriosis. Patients were classified as having active endometriosis during pregnancy, inactive endometriosis during pregnancy, a diagnosis of endometriosis postpregnancy, or no endometriosis. The outcome was SMM, including by a range of life-threatening maternal conditions during pregnancy or up to 42 days postdelivery. We computed rates of SMM and used log binomial regression to assess the association with endometriosis (risk ratio [RR]; 95% CI), adjusted for maternal characteristics. RESULTS: Severe maternal morbidity occurred in 46.2 of 1,000 patients with endometriosis, compared with 30.7 of 1,000 patients without endometriosis. Relative to no exposure, endometriosis was associated with 1.43 times the risk of SMM (95% CI 1.36-1.51). Patients with endometriosis that was active during pregnancy had a greater risk of SMM (RR 1.93; 95% CI 1.76-2.11). Active endometriosis was associated with the risk of severe preeclampsia and eclampsia, severe hemorrhage, hysterectomy, cardiac complications, embolism, shock, sepsis, and intensive care unit admission. Inactive endometriosis was less strongly associated with these outcomes. CONCLUSION: Pregnant patients with endometriosis, especially active endometriosis, have a greater risk of SMM and may benefit from closer follow-up to prevent severe complications of pregnancy.

Ethnicity, Child Sex, and the Likelihood of Marriage in Pregnancy: A Novel Analysis of Gender Inequity.

Objective: We assessed the association between fetal sex and the likelihood of marriage during pregnancy. Methods: We analyzed a cohort of 1,334,911 women who were unmarried at conception and had a live birth between 1990 and 2018 in Quebec, Canada. The exposure was fetal sex, determined by ultrasound. The outcome was marriage during pregnancy. We estimated hazard ratios and 95% confidence intervals (CI) for the association of child sex with the likelihood of marriage during pregnancy according to region of origin. Results: Among women who were unmarried at conception, 13.1% of foreign-born women got married during pregnancy compared with 2.6% of Canadian-born women. Women from the Middle East and North Africa who were pregnant with boys were 1.13 times more likely to marry during pregnancy compared with women who were pregnant with girls (95% CI 1.02-1.26). There was no association among Canadian-born women. Conclusion: Women from some cultural minorities who are pregnant with boys may be more likely to marry during pregnancy in Western settings. Gender inequality may manifest as a preference for sons that influences the likelihood of marriage.

Hyperemesis Gravidarum and the Potential for Cancer: A Longitudinal Cohort Study over Three Decades.

BACKGROUND: Our objective was to assess whether hyperemesis gravidarum is associated with the risk of endodermal, mesodermal, and ectodermal human chorionic gonadotropin (hCG) receptor+ cancer in women. METHODS: We performed a longitudinal cohort study of 1,343,040 women who were pregnant between 1989 and 2019 in Quebec, Canada. We identified women with and without hyperemesis gravidarum and followed them over time to capture incident cancers, grouped by embryonic germ cell layer of origin and organ hCG receptor positivity. We used time-varying Cox regression to model hazard ratios (HR) and 95% confidence intervals (CI) for the association between hyperemesis gravidarum and cancer onset, adjusted for maternal age, comorbidity, multiple gestation, fetal congenital anomaly, socioeconomic deprivation, and time period. RESULTS: Women with hyperemesis gravidarum had a greater risk of endodermal cancer compared with no hyperemesis gravidarum (5.8 vs. 4.8 per 10,000 person-years; HR, 1.36; 95% CI, 1.17-1.57), but not mesodermal or ectodermal cancer. Severe hyperemesis with metabolic disturbance was more strongly associated with cancer from the endodermal germ layer (HR, 1.97; 95% CI, 1.51-2.58). The association between hyperemesis gravidarum and endodermal cancer was driven by bladder (HR, 2.49; 95% CI, 1.37-4.53), colorectal (HR, 1.41; 95% CI, 1.08-1.84), and thyroid (HR, 1.43; 95% CI, 1.09-1.64) cancer. CONCLUSIONS: Women with hyperemesis gravidarum have an increased risk of cancers arising from the endodermal germ cell layer, particularly bladder, colorectal, and thyroid cancers. IMPACT: Future studies identifying the pathways linking hyperemesis gravidarum with endodermal tumors may help improve the detection and management of cancer in women.

Association of PCOS with offspring morbidity: a longitudinal cohort study.

STUDY QUESTION: Do children whose mothers have polycystic ovary syndrome (PCOS) have an increased risk of morbidity? SUMMARY ANSWER: Maternal PCOS is associated with an increased risk of infection, allergy and other childhood morbidity. WHAT IS KNOWN ALREADY: PCOS is associated with higher rates of gestational diabetes, pre-eclampsia and preterm delivery, but the long-term impact on child health is poorly understood. STUDY DESIGN, SIZE, DURATION: We conducted a retrospective longitudinal cohort study of 1 038 375 children in Quebec between 2006 and 2020. PARTICIPANTS/MATERIALS, SETTING, METHODS: We included 7160 children whose mothers had PCOS and 1 031 215 unexposed children. Outcomes included child hospitalization for infectious, allergic, malignant and other diseases before 13 years of age. We estimated hazard ratios (HRs) and 95% CI for the association of PCOS with childhood morbidity in adjusted Cox proportional hazards regression models. MAIN RESULTS AND THE ROLE OF CHANCE: Children exposed to PCOS were hospitalized at a rate of 68.9 (95% CI 66.2-71.8) per 1000 person-years, whereas unexposed children were hospitalized at a rate of 45.3 (95% CI 45.1-45.5) per 1000 person-years. Compared with no exposure, maternal PCOS was associated with 1.32 times the risk of any childhood hospitalization (95% CI 1.26-1.40), 1.31 times the risk of infectious disease hospitalization (95% CI 1.25-1.38) and 1.47 times the risk of allergy-related hospitalization (95% CI 1.31-1.66). Risk of hospitalization was also elevated for childhood metabolic (HR 1.59, 95% CI 1.16-2.18), gastrointestinal (HR 1.72, 95% CI 1.53-1.92), central nervous system (HR 1.74, 95% CI 1.46-2.07) and otologic disorders (HR 1.34, 95% CI 1.26-1.43). Subgroup analyses suggested that there was little difference in the association of PCOS with hospitalization among boys (HR 1.31, 95% CI 1.24-1.39) and girls (HR 1.34, 95% CI 1.26-1.43). LIMITATIONS, REASONS FOR CAUTION: We analyzed severe childhood morbidity requiring hospitalization, not mild diseases treated in ambulatory clinics. We lacked data on ethnicity, education and physical activity, and cannot rule out residual confounding. WIDER IMPLICATIONS OF THE FINDINGS: Our findings suggest that maternal PCOS is associated with an increased risk of childhood morbidity. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by grant PJT-162300 from the Canadian Institutes of Health Research. N.A. acknowledges a career award from the Fonds de recherche du Québec-Santé (296785). The authors declare no competing interests. TRIAL REGISTRATION NUMBER: N/A.

Assisted reproductive technology and childhood morbidity: a longitudinal cohort study.

OBJECTIVE: To evaluate the association between assisted reproductive technology (ART) and offspring morbidity in the first decade of life. DESIGN: Longitudinal cohort study. SETTING: Provincial health registry in Quebec, Canada. PATIENT(S): A total of 797,654 singleton children born between 2008 and 2019, followed up to 2020. INTERVENTION(S): Retrospective, noninterventional study of any ART procedure vs. no ART. MAIN OUTCOME MEASURE(S): Childhood morbidity, including hospitalization for infectious, allergic, malignant, and other diseases, assessed using adjusted Cox proportional hazards regression to estimate hazard ratios (HRs) with 95% confidence intervals (CIs) for the association with ART. We controlled for unmeasured family-level confounders that were shared among siblings through stratified Cox regression. To do so, we restricted the analysis to 10,097 siblings with discordant exposure to ART and compared the risk of outcomes in exposed vs. unexposed siblings. RESULT(S): Compared with no ART, ART was associated with 1.23 times the risk of any hospitalization (95% CI 1.19-1.27), 1.25 times the risk of infectious disease hospitalization (95% CI 1.21-1.29), and 1.25 times the risk of allergy hospitalization (95% CI 1.14-1.38). When we used a sibling design to control for shared genetic and environmental confounders, ART was not associated with a greater risk of childhood hospitalization (HR 0.92, 95% CI 0.78-1.08). CONCLUSION(S): ART is associated with an elevated risk of hospitalization up to 11 years of age, but discordant sibling analysis suggests that the association may be due to genetic, environmental, or other shared familial confounders.

Association of Birth Defects With Child Mortality Before Age 14 Years.

Importance: Causes of death in children with birth defects are poorly understood. Objective: To determine mortality rates by cause of death in children with and without birth defects. Design, Setting, and Participants: This longitudinal cohort study included a population-based sample of 1 037 688 children and was conducted in all hospitals in Quebec, Canada, with 7 700 596 person-years of follow-up between birth and age 14 years (April 1, 2006, to March 31, 2020). Exposures: Presence or absence of a birth defect. Main Outcomes and Measures: Outcomes were all-cause and cause-specific mortality. Hazard ratios (HRs) and 95% CIs were computed for the association between birth defects and mortality with Cox proportional hazards models adjusted for patient characteristics. Results: Among the 1 037 688 children in the cohort, 95 566 had birth defects (56.5% boys). There were 532 542 boys in the cohort (51.3%), and mean (SD) age at the end of follow-up was 7.42 (3.72) years. There were 918 deaths among children with defects, and the mean (SD) age was 0.93 (2.07) years at death; there were 1082 deaths among the 942 122 children without defects, and the mean (SD) age at death was 0.50 (1.51) years. Mortality rates were higher for children with birth defects compared with no defect (1.3 vs 0.2 deaths per 1000 person-years, respectively). Girls (HR, 5.66; 95% CI, 4.96-6.47) and boys (HR, 4.69; 95% CI, 4.15-5.29) with birth defects had an elevated risk of death before 14 years compared with unaffected children. Birth defects were associated with mortality from circulatory (HR, 26.59; 95% CI, 17.73-39.87), respiratory (HR, 23.03; 95% CI, 15.09-35.14), and digestive causes (HR, 31.77; 95% CI, 11.87-85.04), but anomalies were rarely listed as the cause of death. Compared with children with no defect, those with birth defects were at greatest risk of death between 28 and 364 days of life. Conclusions and Relevance: This cohort study of 1 037 688 children suggests that birth defects were strongly associated with mortality owing to circulatory, respiratory, and digestive causes. This finding suggests that the contribution of birth defects may be underestimated in mortality statistics.

Observational study of birth outcomes in children with inborn errors of metabolism.

BACKGROUND: We examined the birth outcomes of children with inborn errors of metabolism detected at birth or later in life. METHODS: We carried out a retrospective cohort study of 1733 children with inborn errors of metabolism and 1,033,693 unaffected children born in Canada between 2006 and 2019. Primary outcomes included preterm birth, low birth weight, congenital anomalies, and other neonatal complications. We estimated adjusted risk ratios (RR) and 95% confidence intervals (CI) for the association of inborn errors of metabolism with each outcome. RESULTS: Children with inborn errors of metabolism had 2.51 times the risk of preterm birth (95% CI 2.27-2.77) and 3.08 times the risk of low birth weight (95% CI 2.77-3.42) compared with unaffected children. Disorders of mineral and lipoprotein metabolism were more strongly associated with adverse birth outcomes. Inborn errors of metabolism were associated with congenital anomalies (RR 2.62; 95% CI 2.36-2.90), particularly abdominal wall defects (RR 8.35; 95% CI 5.18-13.44). Associations were present for errors of metabolism diagnosed both at birth and later in life. CONCLUSIONS: Children with inborn errors of metabolism, whether detected at birth or later, are at high risk of adverse birth outcomes and congenital anomalies. IMPACT: Inborn errors of metabolism may affect fetal development, but the association with adverse birth outcomes is not well characterized. This study indicates that children with inborn errors of metabolism are at risk of preterm birth, neonatal jaundice, congenital anomalies, and a range of other adverse birth outcomes. Mothers of children with inborn errors of metabolism are at risk of preeclampsia and cesarean delivery. Adverse birth outcomes may be a first sign of inborn errors of metabolism that merit increased screening.

Maternal risk factors for paediatric inguinal hernia.

BACKGROUND: Risk factors for paediatric inguinal hernia are poorly understood. This longitudinal cohort study assessed whether children with a maternal history of inguinal hernia or connective tissue disorders have a higher risk of developing inguinal hernias before 13 years of age. METHODS: The study included children followed up between birth and 13 years of age in Quebec, Canada, 2006-2019. Newborns whose mothers had inguinal hernias or connective tissue disorders were followed over time to identify future hospital admissions for inguinal hernia. Cox proportional hazards regression adjusted for patient characteristics was used to estimate hazard ratios (HRs) and 95 per cent confidence intervals for the association between maternal hernia or connective tissue disorders and future childhood hernias. Associations in girls and boys were examined separately. RESULTS: The study included 786 322 children with 6 186 448 person-years of follow-up. There were 6861 children with inguinal hernias, corresponding to an incidence of 11.1 per 10 000 person-years. Children with a maternal history of inguinal hernia had 2.92 (95 per cent c.i. 2.39 to 3.58) times the risk of having inguinal hernias relative to children whose mothers had no such history. Children with a maternal history of connective tissue disorders had 1.30 (1.00 to 1.68) times the risk. Maternal hernias were strongly associated with risk of inguinal hernias in girls (HR 5.34, 3.82 to 7.47), whereas maternal connective tissue disorders were associated with inguinal hernias in boys (HR 1.35, 1.02 to 1.79). CONCLUSION: Paediatric inguinal hernias may be associated with maternal inguinal hernias and connective tissue disorders, but the underlying reason for this relationship requires further investigation.

In this study of 786 322 children in Canada from 2006 to 2019, it was found that children whose mothers had an inguinal hernia or connective tissue disorder were more at risk of developing a hernia themselves. Repairs for inguinal hernia are among the most common operations performed in children. The results showed that girls whose mothers had an inguinal hernia had more than five times the risk of developing an inguinal hernia before 13 years of age. Boys whose mothers had connective tissue disorders had a 35 per cent greater risk of inguinal hernia. These findings suggest that inguinal hernias may be inherited.

Matters of the Heart: Case-Crossover Analysis of Myocardial Infarction on Valentine's Day.

We studied the risk of myocardial infarction on Valentine's Day. We conducted a case-crossover study of 51,450 adults with myocardial infarctions in February, 1989-2019. The exposure was Valentine's Day, and the 2 days before and after Valentine's Day. We estimated odds ratios (OR) to compare days when myocardial infarction occurred with neighboring control days. Compared with other days, Valentine's Day was associated with lower odds of myocardial infarction the following day for men (OR 0.91, 95% confidence interval 0.85-0.98), but not for men and women combined (OR 0.95, 95% confidence interval 0.91-1.01). Risk of myocardial infarction in men is lower the day after Valentine's Day.

Nous avons étudié le risque de subir un infarctus du myocarde le jour de la Saint-Valentin. Nous avons réalisé une étude selon la méthode cas-croisé portant sur 51 450 adultes ayant subi un infarctus du myocarde en février entre 1989 et 2019. La période d'exposition était le jour de la Saint-Valentin ainsi que les 2 jours précédant et suivant celui-ci. Nous avons estimé les rapports de cotes (RC) pour comparer les jours où étaient survenus des infarctus du myocarde et les jours témoins voisins de cette date. Comparativement aux autres jours, le jour de la Saint-Valentin était associé à une probabilité plus faible d'infarctus du myocarde le lendemain chez les hommes (RC 0,91, intervalle de confiance à 95 % : de 0,85 à 0,98), mais pas chez les hommes et les femmes analysés ensemble (RC 0,95, intervalle de confiance à 95 % : de 0,91 à 1,01). Le risque d'infarctus du myocarde chez les hommes est plus faible le lendemain de la Saint-Valentin.

Risk of Severe Maternal Morbidity After Bariatric Surgery: Retrospective Cohort Study.

OBJECTIVE: We assessed whether bariatric surgery before pregnancy lowers the risk of severe maternal morbidity to a level comparable to no obesity. SUMMARY OF BACKGROUND DATA: Obesity is a risk factor for severe maternal morbidity, but the potential for bariatric surgery to reduce the risk has not been studied. METHODS: We analyzed a retrospective cohort of 2,412,075 deliveries between 1989 and 2019 in Quebec, Canada. The main exposure measures were bariatric surgery before pregnancy and obesity without bariatric surgery, compared with no obesity. The outcome was severe maternal morbidity, a composite of life-threatening pregnancy complications. We estimated risk ratios (RR) and 95% confidence intervals (CI) for the association between bariatric surgery and severe maternal morbidity, adjusted for maternal characteristics. RESULTS: A total of 2654 deliveries (0.1%) were in women who had bariatric surgery, and 70,041 (29.0 per 1000) were in women who had severe maternal morbidity. Risk of severe maternal morbidity was not significantly elevated for bariatric surgery (RR 1.20; 95% CI 0.98-1.46), but was greater for obesity compared with no obesity (RR 1.60; 95% CI 1.55-1.64). Bariatric surgery was not associated with morbidities such as severe preeclampsia, sepsis, and cardiac complications compared with no obesity, but obesity was associated with elevated risks of these and other severe morbidities. Bariatric surgery was associated, however, with intensive care unit admission, compared with no obesity. CONCLUSIONS: Pregnant women with prior bariatric surgery have similar risks as nonobese women for most types of severe maternal morbidity, except for intensive care unit admission.