Use of Latent Class Analysis to Predict Intensive Care Unit Admission and Mortality in Children with a Major Congenital Anomaly.

OBJECTIVE: To define major congenital anomaly (CA) subgroups and assess outcome variability based on defined subgroups. STUDY DESIGN: This population-based cohort study used registries in Denmark for children born with a major CA between January 1997 and December 2016, with follow-up until December 2018. We performed a latent class analysis (LCA) using child and family clinical and sociodemographic characteristics present at birth, incorporating additional variables occurring until age of 24 months. Cox proportional hazards regression models estimated hazard ratios (HRs) of pediatric mortality and intensive care unit (ICU) admissions for identified LCA classes. RESULTS: The study included 27 192 children born with a major CA. Twelve variables led to a 4-class solution (entropy = 0.74): (1) children born with higher income and fewer comorbidities (55.4%), (2) children born to young mothers with lower income (24.8%), (3) children born prematurely (10.0%), and (4) children with multiorgan involvement and developmental disability (9.8%). Compared with those in Class 1, mortality and ICU admissions were highest in Class 4 (HR = 8.9, 95% CI = 6.4-12.6 and HR = 4.1, 95% CI = 3.6-4.7, respectively). More modest increases were observed among the other classes for mortality and ICU admissions (Class 2: HR = 1.7, 95% CI = 1.1-2.5 and HR = 1.3, 95% CI = 1.1-1.4, respectively; Class 3: HR = 2.5, 95% CI = 1.5-4.2 and HR = 1.5, 95% CI = 1.3-1.9, respectively). CONCLUSIONS: Children with a major CA can be categorized into meaningful subgroups with good discriminative ability. These groupings may be useful for risk-stratification in outcome studies.

Readiness for behaviour change after gestational diabetes mellitus: A prospective cohort study.

AIMS: Women with gestational diabetes mellitus (GDM) have a high risk of developing type 2 diabetes (T2D). Readiness for behaviour change to mitigate this risk may be low after pregnancy and may further decrease over time without appropriate interventions. This study aimed to evaluate readiness for behaviour change in the first and second postpartum years in women with recent GDM to determine the best timing for lifestyle interventions to prevent T2D. METHODS: This study included a subset of women with GDM between 2009 and 2013 in Ontario, Canada from a larger prospective cohort study who completed a survey in the first and second postpartum years (N = 329). The primary outcome was stage of readiness for behaviour change for diet and physical activity, compared between the first and second postpartum years. RESULTS: The mean age was 34.3 ± 4.4 standard deviation (SD) years and mean pre-pregnancy body-mass index (BMI) was 26.7 ± 6.9 kg/m2. In the first postpartum year, 86% of women reported a pre-action stage of change, which was 87% by the second postpartum year (p = 0.646). Non-Caucasian ethnicity was associated with lower odds of being in the action stage of readiness for behaviour change overall and for physical activity in both time periods. CONCLUSIONS: Most postpartum women with recent GDM are in a pre-action stage of change after delivery, which does not increase by the second postpartum year. Behavioural interventions should continue to be prioritized in postpartum women with GDM to optimize this slim window of opportunity for T2D prevention.

Trends in rate of hypertensive disorders of pregnancy and associated morbidities in Canada: a population-based study (2012-2021).

BACKGROUND: Hypertensive disorders of pregnancy (HDP) are a leading cause of severe maternal morbidity (SMM). We sought to explore trends in HDP and related morbidity outcomes in Canada. METHODS: In this retrospective population-based study, we used hospital discharge data from Canada, excluding Quebec, to identify females who had an HDP diagnosis during a birth admission between 2012 and 2021. We analyzed temporal and geographical trends in HDP, as well as temporal trends in adverse outcomes associated with HDP. RESULTS: Among 2 804 473 hospital admissions for birth between 2012 and 2021, the rate of any HDP increased from 6.1% to 8.5%, including pre-existing hypertension (0.6% to 0.9%), gestational hypertension (3.9% to 5.1%), and preeclampsia (1.6% to 2.6%). For 2017-2021 combined, relative to Ontario (6.9%), HDP were significantly more prevalent in nearly all other Canadian regions. For example, in Newfoundland and Labrador, the rate was 10.7% (unadjusted rate ratio 1.56, 95% confidence interval 1.49-1.63). Among females with any HDP, rates of cesarean delivery rose from 42.0% in 2012 to 44.3% in 2021, as did acute renal failure (0.4% to 0.6%), while rates of early preterm delivery, intrauterine fetal death, maternal hospital length of stay (≥ 7 d), admission to the maternal intensive care unit, severe hemorrhage, and SMM trended downward. INTERPRETATION: The rate of HDP has risen across Canada, with a concomitant decline in some HDP-associated morbidities. Ongoing surveillance of HDP is needed to assess the factors associated with temporal trends, including the effectiveness of evolving HDP prevention and management efforts.

Patterns of multiple chronic conditions in pregnancy: Population-based study using latent class analysis.

BACKGROUND: Adults with multiple chronic conditions (MCC) are a heterogeneous population with elevated risk of future adverse health outcomes. Yet, despite the increasing prevalence of MCC globally, data about MCC in pregnancy are scarce. OBJECTIVES: To estimate the population prevalence of MCC in pregnancy and determine whether certain types of chronic conditions cluster together among pregnant women with MCC. METHODS: We conducted a population-based cohort study in Ontario, Canada, of all 15-55-year-old women with a recognised pregnancy, from 2007 to 2020. MCC was assessed from a list of 22 conditions, identified using validated algorithms. We estimated the prevalence of MCC. Next, we used latent class analysis to identify classes of co-occurring chronic conditions in women with MCC, with model selection based on parsimony, clinical interpretability and statistical fit. RESULTS: Among 2,014,508 pregnancies, 324,735 had MCC (161.2 per 1000, 95% confidence interval [CI] 160.6, 161.8). Latent class analysis resulted in a five-class solution. In four classes, mood and anxiety disorders were prominent and clustered with one additional condition, as follows: Class 1 (22.4% of women with MCC), osteoarthritis; Class 2 (23.7%), obesity; Class 3 (15.8%), substance use disorders; and Class 4 (22.1%), asthma. In Class 5 (16.1%), four physical conditions clustered together: obesity, asthma, chronic hypertension and diabetes mellitus. CONCLUSIONS: MCC is common in pregnancy, with sub-types dominated by co-occurring mental and physical health conditions. These data show the importance of preconception and perinatal interventions, particularly integrated care strategies, to optimise treatment and stabilisation of chronic conditions in women with MCC.

Miscarriage after SARS-CoV-2 vaccination: A population-based cohort study.

OBJECTIVE: To evaluate the risk of miscarriage following SARS-CoV-2 vaccination, while accounting for the competing risk of induced abortion. DESIGN: Population-based cohort study. SETTING: Ontario, Canada. PARTICIPANTS: Women aged 15-50 years with a confirmed pregnancy at ≤19 completed weeks' gestation. METHODS: Exposure to first SARS-CoV-2 vaccination, handled in a time-varying manner, was defined as (i) unvaccinated, (ii) remotely vaccinated >28 days before the estimated conception date or (iii) recently vaccinated ≤28 days before conception and up to 120 days after conception. MAIN OUTCOME MEASURES: The outcome was miscarriage, occurring between the estimated date of conception and up to 19 completed weeks of pregnancy. Fine-Grey hazard models, accounting for the competing risk of induced abortion, generated hazard ratios (aHR), adjusted for socio-demographic factors, comorbidities, and biweekly periods. RESULTS: Included were 246 259 pregnant women, of whom 34% received a first SARS-CoV-2 vaccination. Miscarriage occurred at a rate of 3.6 per 10 000 person-days among remotely vaccinated women and 3.2 per 10 000 person-days among those recently vaccinated, in contrast to a rate of 1.9 per 10 000 person-days among unvaccinated women, with corresponding aHR of 0.98 (95% confidence interval [CI] 0.91-1.07) and 1.00 (95% CI 0.93-1.08). CONCLUSIONS: SARS-CoV-2 vaccination was not associated with miscarriage while accounting for the competing risk of induced abortion. This study reiterates the importance of including pregnant women in new vaccine clinical trials and registries, and the rapid dissemination of vaccine safety data.

Procedural abortion, provider-initiated preterm delivery and survival in pregnant people with cancer: A population-based cohort study.

OBJECTIVE: To assess whether procedural-induced abortion or provider-initiated preterm delivery are associated with improved survival in pregnant people with cancer. DESIGN: Retrospective population-based cohort study. SETTING: Provinces of Alberta and Ontario, Canada, 2003-2016. POPULATION: Females aged 18-50 years diagnosed with cancer at <20 weeks' (for the assessment of procedural-induced abortion) or <37 weeks' gestation (for the assessment of provider-initiated delivery). METHODS: Cox proportional hazard models assessed all-cause mortality in relation to procedural-induced abortion and provider-initiated preterm delivery, adjusting for cancer site, stage at diagnosis and age. Meta-analysis pooled the results across both provinces. MAIN OUTCOME MEASURES: All cause mortality. RESULTS: There were 512 pregnant people diagnosed with cancer at <20 weeks' gestation and 782 diagnosed with cancer at <37 weeks' gestation. Neither procedural-induced abortion (adjusted hazard ratio [aHR] = 1.39, 95% CI: 0.32-6.17) nor provider-initiated preterm delivery (aHR = 1.17, 95% CI: 0.76-1.81) were associated with improved survival following adjustment for age, stage at diagnosis and cancer site. CONCLUSIONS: Neither procedural-induced abortion nor provider-initiated preterm birth was associated with improved survival in pregnant people diagnosed with cancer; however, these obstetric interventions are highly personal decisions best decided by the pregnant person in consultation with their care providers.

Diabetes mellitus in pregnancy across Canada.

BACKGROUND: Contemporary estimates of diabetes mellitus (DM) rates in pregnancy are lacking in Canada. Accordingly, this study examined trends in the rates of type 1 (T1DM), type 2 (T2DM) and gestational (GDM) DM in Canada over a 15-year period, and selected adverse pregnancy outcomes. METHODS: This study used repeated cross-sectional data from the Canadian Institute of Health Information (CIHI) hospitalization discharge abstract database (DAD). Maternal delivery records were linked to their respective birth records from 2006 to 2019. The prevalence of T1DM, T2DM and GDM were calculated, including relative changes over time, assessed by a Cochrane-Armitage test. Also assessed were differences between provinces and territories in the prevalence of DM. RESULTS: Over the 15-year study period, comprising 4,320,778 hospital deliveries in Canada, there was a statistically significant increase in the prevalence of GDM and T1DM and T2DM. Compared to pregnancies without DM, all pregnancies with any form of DM had higher rates of hypertension and Caesarian delivery, and also adverse infant outcomes, including major congenital anomalies, preterm birth and large-for-gestational age birthweight. CONCLUSION: Among 4.3 million pregnancies in Canada, there has been a rise in the prevalence of DM. T2DM and GDM are expected to increase further as more overweight women conceive in Canada.

Mental Illness in the 2 Years Prior to Pregnancy in a Population With Traumatic Brain Injury: A Cross-Sectional Study: La maladie mentale dans les deux ans précédant une grossesse dans une population souffrant de lésion cérébrale traumatique : une étude transversale.

OBJECTIVE: Existing studies, in mostly male samples such as veterans and athletes, show a strong association between traumatic brain injury (TBI) and mental illness. Yet, while an understanding of mental health before pregnancy is critical for informing preconception and perinatal supports, there are no data on the prevalence of active mental illness before pregnancy in females with TBI. We examined the prevalence of active mental illness ≤2 years before pregnancy (1) in a population with TBI, and (2) in subgroups defined by sociodemographic, health, and injury-related characteristics, all compared to those without TBI. METHOD: This population-based cross-sectional study was completed in Ontario, Canada, from 2012 to 2020. Modified Poisson regression generated adjusted prevalence ratios (aPRs) of active mental illness ≤2 years before pregnancy in 15,585 females with TBI versus 846,686 without TBI. We then used latent class analysis to identify subgroups with TBI according to sociodemographic, health, and injury-related characteristics and subsequently compared them to females without TBI on their outcome prevalence. RESULTS: Females with TBI had a higher prevalence of active mental illness ≤2 years before pregnancy than those without TBI (44.1% vs. 25.9%; aPR 1.46, 95% confidence interval, 1.43 to 1.49). There were 3 TBI subgroups, with Class 1 (low-income, past assault, recent TBI described as intentional and due to being struck by/against) having the highest outcome prevalence. CONCLUSIONS: Females with TBI, and especially those with a recent intentional TBI, have a high prevalence of mental illness before pregnancy. They may benefit from mental health screening and support in the post-injury, preconception, and perinatal periods. PLAIN LANGUAGE TITLE: Mental illness in the 2 years before pregnancy in a population with traumatic brain injury.

Research has shown a strong association between traumatic brain injury (TBI) and mental illness. Most previous studies have been conducted in primarily male samples, like veterans and professional athletes. Understanding mental health before pregnancy is important for deciding what supports people need before and during pregnancy. However, there are no studies on the frequency of mental illness in females with TBI before a pregnancy. We examined the frequency of mental illness 2 years before pregnancy in a population with TBI, and in subgroups defined by different social, health, and injury-related characteristics, compared to those without TBI. We undertook a population-wide study of all females with and without TBI in Ontario, Canada, with a birth in 2012­2020. We used statistical models to compare these groups on the presence of mental illness in the 2 years before pregnancy, before and after accounting for social and health characteristics. We also identified subgroups with TBI according to their social (e.g., poverty), health (e.g., chronic conditions), and injury-related characteristics (e.g., cause of injury) and subsequently compared them to females without TBI on their frequency of mental illness in the 2 years before pregnancy. Forty-four percent of females with TBI had mental illness in the 2 years before pregnancy compared to 25% of those without TBI. There were 3 TBI subgroups. Females with low-income, past assault, and injuries that were described as being intentional had the highest frequency of mental illness in the 2 years before pregnancy. Females with TBI may benefit from mental health screening and support post-injury and around the time of pregnancy.

Maternal Deaths by Suicide and Drug Overdose in Two Canadian Provinces; Retrospective Review.

OBJECTIVES: To identify and review factors associated with maternal deaths by suicide and drug overdose in the Canadian Coroner and Medical Examiners Database, from 2017 to 2019. METHODS: We identified potential maternal deaths in Ontario and British Columbia by searching the Canadian Coroner and Medical Examiners Database narratives of deaths to females 10 to 60 years old for pregnancy-related terms. Identified narratives were then qualitatively reviewed in quadruplicate to determine if they were maternal deaths by suicide or drug overdose, and to extract information on maternal characteristics, the manner of death, and factors associated with each death. RESULTS: Of the 90 deaths identified in this study, 15 (16.7%) were due to suicide and 20 (22.2%) were due to a drug overdose. These deaths occurred in women of varying ages and across the pregnancy-postpartum period. Among the suicides, 10 were by hanging, and among the overdose-related deaths, 15 had fentanyl detected. Notably, 13 (37.1%) of the 35 deaths to suicide or drug overdose occurred beyond 42 days after pregnancy, 19 (54.3%) followed a miscarriage or induced abortion, and in 23 (65.7%) there was an established history of mental health illness. Substance use disorders were documented in 4 of the 15 suicides (26.7%), and 18 of the 20 overdose-related deaths (90.0%). CONCLUSIONS: Suicide and drug overdose may contribute more to maternal deaths in Canada than previously realized. Programs are needed to identify women at risk of these outcomes and to intervene during pregnancy and beyond the conventional postpartum period.

Maternal Deaths Using Coroner's Data: A Latent Class Analysis.

OBJECTIVE: Knowledge regarding the antecedent clinical and social factors associated with maternal death around the time of pregnancy is limited. This study identified distinct subgroups of maternal deaths using population-based coroner's data, and that may inform ongoing preventative initiatives. METHODS: A detailed review of coroner's death files was performed for all of Ontario, Canada, where there is a single reporting mechanism for maternal deaths. Deaths in pregnancy, or within 365 days thereafter, were identified within the Office of the Chief Coroner for Ontario database, 2004-2020. Variables related to the social and clinical circumstances surrounding the deaths were abstracted in a standardized manner from each death file, including demographics, forensic information, nature and cause of death, and antecedent health and health care factors. These variables were then entered into a latent class analysis (LCA) to identify distinct types of deaths. RESULTS: Among 273 deaths identified in the study period, LCA optimally identified three distinct subgroups, namely, (1) in-hospital deaths arising during birth or soon thereafter (52.7% of the sample); (2) accidents and unforeseen obstetric complications also resulting in infant demise (26.3%); and (3) out-of-hospital suicides occurring postpartum (21.0%). Physical injury (22.0%) was the leading cause of death, followed by hemorrhage (16.8%) and overdose (13.3%). CONCLUSION: Peri-pregnancy maternal deaths can be classified into three distinct sub-types, with somewhat differing causes. These findings may enhance clinical and policy development aimed at reducing pregnancy mortality.

Building Healthy Babies: A Mixed-Methods Needs Assessment for a Pre-Conception Program in Ontario.

OBJECTIVES: The objective of this study was to gather Ontario clinicians' and public members' views on the design of a pre-conception patient education program. METHODS: In this mixed-methods study, online surveys comprised of rank order, multiple choice, and short answer questions were completed by clinicians and public members. Semi-structured focus groups consisting of 2-6 participants each were then held via videoconference. Demographic variables and survey responses were analyzed quantitatively using descriptive and summary statistics. Descriptive thematic qualitative analysis using the constant comparative method of grounded theory was completed on each transcript to generate themes. RESULTS: A total of 168 public members and 43 clinicians in Ontario completed surveys, while 11 clinicians and 11 public members participated in the focus groups. A pre-conception program in Ontario was felt to be important. An individual appointment with a primary care provider was the favoured program format per survey responses, whereas a virtual format with an interactive component was preferred among focus group participants. Important topics to include were pre-conception health (infertility, genetic screening, folic acid), prenatal and postpartum counselling (diet, activity, substance use, prenatal care, postpartum course), and medical optimization in pregnancy (high-risk medical conditions, medications, mental health). Both groups emphasized the need to consider accommodations for marginalized populations and various cultures and languages. CONCLUSION: A standardized pre-conception patient education program is felt to be of high value by Ontario clinicians and public members. A pre-conception program may help improve obstetrical outcomes and decrease rates of major congenital anomalies in Ontario.

Short-Term Adverse Outcomes After Mifepristone-Misoprostol Versus Procedural Induced Abortion : A Population-Based Propensity-Weighted Study.

BACKGROUND: Prior studies comparing first-trimester pharmaceutical induced abortion (IA) with procedural IA were prone to selection bias, were underpowered to assess serious adverse events (SAEs), and did not account for confounding by indication. Starting in 2017, mifepristone-misoprostol was dispensed at no cost in outpatient pharmacies across Ontario, Canada. OBJECTIVE: To compare short-term risk for adverse outcomes after early IA by mifepristone-misoprostol versus by procedural IA. DESIGN: Population-based cohort study. SETTING: Ontario, Canada. PATIENTS: All women who had first-trimester IA. MEASUREMENTS: A total of 39 856 women dispensed mifepristone-misoprostol as outpatients were compared with 65 176 women undergoing procedural IA at 14 weeks' gestation or earlier within nonhospital outpatient clinics (comparison 1). A total of 39 856 women prescribed mifepristone-misoprostol were compared with 8861 women undergoing ambulatory hospital-based procedural IA at an estimated 9 weeks' gestation or less (comparison 2). The primary composite outcome was any SAE within 42 days after IA, including severe maternal morbidity, end-organ damage, intensive care unit admission, or death. A coprimary broader outcome comprised any SAE, hemorrhage, retained products of conception, infection, or transfusion. Stabilized inverse probability of treatment weighting accounted for confounding between exposure groups. RESULTS: Mean age at IA was about 29 years (SD, 7); 33% were primigravidae. Six percent resided in rural areas, and 25% resided in low-income neighborhoods. In comparison 1, SAEs occurred among 133 women after mifepristone-misoprostol IA (3.3 per 1000) versus 114 after procedural IA (1.8 per 1000) (relative risk [RR], 1.87 [95% CI, 1.44 to 2.43]; absolute risk difference [ARD], 1.5 per 1000 [CI, 0.9 to 2.2]). The respective rates of any adverse event were 28.9 versus 12.4 per 1000 (RR, 2.33 [CI, 2.11 to 2.57]; ARD, 16.5 per 1000 [CI, 14.5 to 18.4]). In comparison 2, SAEs occurred among 133 (3.4 per 1000) and 27 (3.3 per 1000) women, respectively (RR, 1.04 [CI, 0.61 to 1.78]). The respective rates of any adverse event were 31.2 versus 24.9 per 1000 (RR, 1.25 [CI, 1.04 to 1.51]). LIMITATION: A woman prescribed mifepristone-misoprostol may not have taken the medication, and the exact gestational age at IA was not always known. CONCLUSION: Although rare, short-term adverse events are more likely after mifepristone-misoprostol IA than procedural IA, especially for less serious adverse outcomes. PRIMARY FUNDING SOURCE: Canadian Institutes of Health Research.

Pre-Pregnancy eGFR and the Risk of Adverse Maternal and Fetal Outcomes: A Population-Based Study.

SIGNIFICANCE STATEMENT: Pregnancies in women with CKD carry greater risk than pregnancies in the general population. The small number of women in prior studies has limited estimates of this risk, especially among those with advanced CKD. We report the results of a population-based cohort study in Ontario, Canada, that assessed more than 500,000 pregnancies, including 600 with a baseline eGFR < 60 ml/min per 1.73 m 2 . The investigation demonstrates increases in risk of different adverse maternal and fetal outcomes with lower eGFR and further risk elevation with baseline proteinuria. BACKGROUND: CKD is a risk factor for pregnancy complications, but estimates for adverse outcomes come largely from single-center studies with few women with moderate or advanced stage CKD. METHODS: To investigate the association between maternal baseline eGFR and risk of adverse pregnancy outcomes, we conducted a retrospective, population-based cohort study of women (not on dialysis or having had a kidney transplant) in Ontario, Canada, who delivered between 2007 and 2019. The study included 565,907 pregnancies among 462,053 women. Administrative health databases captured hospital births, outpatient laboratory testing, and pregnancy complications. We analyzed pregnancies with serum creatinine measured within 2 years of conception up to 30 days after conception and assessed the impact of urine protein where available. RESULTS: The risk of major maternal morbidity, preterm delivery, and low birthweight increased monotonically across declining eGFR categories, with risk increase most notable as eGFR dropped below 60 ml/min per 1.73 m 2 . A total of 56 (40%) of the 133 pregnancies with an eGFR <45 ml/min per 1.73 m 2 resulted in delivery under 37 weeks, compared with 10% of pregnancies when eGFR exceeded 90 ml/min per 1.73 m 2 . Greater proteinuria significantly increased risk within each eGFR category. Maternal and neonatal deaths were rare regardless of baseline eGFR (<0.3% of all pregnancies). Only 7% of women with an eGFR <45 ml/min per 1.73 m 2 received dialysis during or immediately after pregnancy. CONCLUSIONS: We observed higher rates of adverse pregnancy outcomes in women with low eGFR with concurrent proteinuria. These results can help inform health care policy, preconception counseling, and pregnancy follow-up in women with CKD.

Using multi-level regression to determine associations and estimate causes and effects in clinical anesthesia due to patient, practitioner and hospital or health system practice variability.

In this research methods tutorial of clinical anesthesia, we will explore techniques to estimate the influence of a myriad of factors on patient outcomes. Big data that contain information on patients, treated by individual anesthesiologists and surgical teams, at different hospitals, have an inherent multi-level data structure (Fig. 1). While researchers often attempt to determine the association between patient factors and outcomes, that does not provide clinicians with the whole story. Patient care is clustered together according to clinicians and hospitals where they receive treatment. Therefore, multi-level regression models are needed to validly estimate the influence of each factor at each level. In addition, we will explore how to estimate the influence that variability-for example, one anesthesiologist deciding to do one thing, while another takes a different approach-has on outcomes for patients, using the intra-class correlation coefficient for continuous outcomes and the median odds ratio for binary outcomes. From this tutorial, you should acquire a clearer understanding of how to perform and interpret multi-level regression modeling and estimate the influence of variable clinical practices on patient outcomes in order to answer common but complex clinical questions. Fig. 1 Infographics.

The association between offspring birthweight and future risk of maternal diabetes: A population-based study.

AIMS: As an indicator of maternal cardiometabolic health, newborn birthweight may be an important predictor of maternal type 2 diabetes mellitus (diabetes). We evaluated the relation between offspring birthweight and onset of maternal diabetes after pregnancy. METHODS: This retrospective cohort study used linked population-based health databases from Ontario, Canada. We included women aged 16-50 years without pre-pregnancy diabetes, and who had a live birth between 2006 and 2014. We used Cox proportional hazard regression to evaluate the association between age- and sex-standardized offspring birthweight percentile categories and incident maternal diabetes, while adjusting for maternal age, parity, year, ethnicity, gestational diabetes (GDM) and hypertensive disorders of pregnancy (HDP). Results were further stratified by the presence of GDM in the index pregnancy. RESULTS: Of 893,777 eligible participants, 14,329 (1.6%) women were diagnosed with diabetes over a median (IQR) of 4.4 (1.5-7.4) years of follow-up. There was a continuous positive relation between newborn birthweight above the 75th percentile and maternal diabetes. Relative to a birthweight between the 50th and 74.9th percentiles, women whose newborn had a birthweight between the 97th and 100th percentiles had an adjusted hazards ratio (aHR) of diabetes of 2.30 (95% CI 2.16-2.46), including an aHR of 2.01 (95% CI 1.83-2.21) among those with GDM, and 2.59 (2.36-2.84) in those without GDM. CONCLUSIONS: A higher offspring birthweight signals an increased risk of maternal diabetes, offering another potentially useful way to identify women especially predisposed to diabetes.

The association between immigration status and the development of type 2 diabetes in women with a prior diagnosis of gestational diabetes: A population-based study.

AIMS: The aim of this study was to examine the influence of immigration status and region of origin on the risk of type 2 diabetes in women with prior gestational diabetes (GDM). METHODS: This retrospective population-based cohort study included women with gestational diabetes (GDM) aged 16 to 50 years in Ontario, Canada, who gave birth between 2006 and 2014. We compared the incidence of type 2 diabetes after delivery between long-term residents and immigrants-overall, by time since immigration and by region of-using Cox regression adjusted for age, year, neighbourhood income, rurality, infant birth weight and presence of hypertensive disorders of pregnancy (HDP). RESULTS: Among 38,515 women with prior GDM (42% immigrants), immigrants had a significantly higher risk of type 2 diabetes compared with long-term residents (adjusted hazard ratio [HR] 1.19, 95% confidence interval [CI] 1.13-1.26), with no meaningful difference based on time since immigration. The highest adjusted relative risks of type 2 diabetes compared with long-term residents were found for immigrants from Sub-Saharan Africa (HR 1.63, 95% CI 1.40-1.90), Latin America/Caribbean (HR 1.44, 95% CI 1.28-1.62) and South Asia (HR 1.34, 95% CI 1.25-1.44). CONCLUSIONS: Immigration is associated with a significantly higher risk of type 2 diabetes after GDM, particularly for women from certain low- and middle-income countries. Diabetes prevention strategies will need to consider the unique needs of immigrants from these regions.

Risk of recurrent severe maternal morbidity: a population-based study.

BACKGROUND: Severe maternal morbidity is a composite indicator of maternal health and obstetrical care. Little is known about the risk of recurrent severe maternal morbidity in a subsequent delivery. OBJECTIVE: This study aimed to estimate the risk of recurrent severe maternal morbidity in the next delivery after a complicated first delivery. STUDY DESIGN: We analyzed a population-based cohort study of women with at least 2 singleton hospital deliveries between 1989 and 2021 in Quebec, Canada. The exposure was severe maternal morbidity in the first hospital-recorded delivery. The study outcome was severe maternal morbidity at the second delivery. Log-binomial regression models adjusted for maternal and pregnancy characteristics were used to generate relative risks and 95% confidence intervals comparing women with and without severe maternal morbidity at first delivery. RESULTS: Among 819,375 women, 43,501 (3.2%) experienced severe maternal morbidity in the first delivery. The rate of severe maternal morbidity recurrence at second delivery was 65.2 vs 20.3 per 1000 in women with and without previous severe maternal morbidity (adjusted relative risk, 3.11; 95% confidence interval, 2.96-3.27). The adjusted relative risk for recurrence of severe maternal morbidity was greatest among women who had ≥3 different types of severe maternal morbidity at their first delivery, relative to those with none (adjusted relative risk, 5.50; 95% confidence interval, 4.26-7.10). Women with cardiac complication at first delivery had the highest risk of severe maternal morbidity in the next delivery. CONCLUSION: Women who experience severe maternal morbidity have a relatively high risk of recurrent morbidity in the subsequent pregnancy. In women with severe maternal morbidity, these study findings have implications for prepregnancy counseling and maternity care in the next pregnancy.

Pre-phototherapy total serum bilirubin levels in extremely preterm infants.

BACKGROUND: Extremely preterm infants are prone to hyperbilirubinemia and its sequelae. Currently recommended thresholds for initiating phototherapy in these newborns are consensus-based (CB). METHODS: A multi-site retrospective cohort study of 642 infants born at 240/7 to 286/7 weeks' gestation, between January 2013 and June 2017, was conducted at three NICUs in Canada. Pre-phototherapy TSB percentile levels at 24 h of age were generated and contrasted with published CB thresholds. RESULTS: Among infants born 240/7 to 256/7 weeks' gestation, the differences between our TSB percentiles vs. the CB threshold of 85.0 µmol/L were 10.0 µmol/L (95% CI, 6.0-16.0) at the 75th percentile and 35.3 µmol/L (95% CI, 26.1-42.8) at the 95th percentile. Respectively, among infants born at 260/7 to 276/7 weeks, differences were 19.4 µmol/L (95% CI, 16.8-23.4) and 43.3 µmol/L (95% CI, 34.7-46.9). Born at 280/7 to 286/7 weeks' gestation, differences between our 75th and 95th TSB percentiles and the CB threshold of 103 µmol/L were 6.9 µmol/L (95% CI, 3.2-12.0) and 36.0 µmol/L (95% CI, 31.0-44.3), respectively. CONCLUSIONS: We provide statistically derived pre-phototherapy TSB levels that may clarify patterns of pre-phototherapy TSB levels in extremely preterm infants. IMPACT: We present statistically derived pre-phototherapy total serum bilirubin levels in a cohort of extremely preterm infants. Most of these preterm infants received phototherapy-some at below currently published thresholds. There are notable differences between our statistically derived pre-phototherapy TSB levels and currently published lower limit TSB thresholds for phototherapy. Our study results assist in the understanding of pre-phototherapy TSB levels in extremely preterm infants.

Receipt of adequate prenatal care for privately sponsored versus government-assisted refugees in Ontario, Canada: a population-based cohort study.

BACKGROUND: Canada has 2 main streams of resettlement: government-assisted refugees and privately sponsored refugees, whereby citizens can privately sponsor refugees and provide resettlement services, including health care navigation. Our objective was to compare receipt of adequate prenatal care among privately sponsored and government-assisted refugees. METHODS: This population-based study used linked health administrative and demographic databases. We included all resettled refugees classified as female who landed in Ontario, Canada, between April 2002 and May 2017, and who had a live birth or stillbirth conceived at least 365 days after their landing date. Our primary outcome - adequacy of prenatal care - was a composite that comprised receipt of a first-trimester prenatal visit, the number of prenatal care visits recommended by the Society of Obstetricians and Gynaecologists of Canada and a prenatal fetal anatomy ultrasound. We accounted for potential confounding with inverse probability of treatment weighting, using a propensity score. RESULTS: We included 2775 government-assisted and 2374 privately sponsored refugees. Compared with privately sponsored refugees (62.3% v. 69.3%), government-assisted refugees received adequate prenatal care less often, with a weighted relative risk of 0.93 (95% confidence interval 0.88-0.95). INTERPRETATION: Among refugees resettled to Canada, a government-assisted resettlement model was associated with receiving less adequate prenatal care than a private sponsorship model. Government-assisted refugees may benefit from additional support in navigating health care beyond the first year after arrival.

Prescription of oxycodone versus codeine after childbirth and risk of persistent opioid use: a population-based cohort study.

BACKGROUND: Oxycodone is increasingly prescribed for postpartum analgesia in lieu of codeine owing to concerns regarding the neonatal safety of codeine during lactation. We examined whether initiation of oxycodone after delivery was associated with an increased risk of persistent opioid use relative to initiation of codeine. METHODS: We conducted a population-based cohort study of people who filled a prescription for either codeine or oxycodone within 7 days of discharge from hospital after delivery between Sept. 1, 2012, and June 30, 2020. The primary outcome was persistent opioid use, defined as 1 or more additional prescriptions for an opioid within 90 days of the first postpartum prescription and 1 or more additional prescriptions in the 91 to 365 days thereafter. We used inverse probability of treatment weighting to assess the risk of persistent postpartum opioid use, comparing people who initiated oxycodone with those who initiated codeine. RESULTS: Over the 8-year study period, we identified 70 607 people who filled an opioid prescription within 7 days of discharge from hospital: 21 308 (30.2%) received codeine and 49 299 (69.8%) oxycodone. Compared with people who filled a prescription for codeine, receipt of oxycodone was not associated with persistent opioid use (relative risk [RR] 1.04, 95% confidence interval [CI] 0.91-1.20). We found an association between a prescription for oxycodone and persistent use after vaginal delivery (RR 1.63, 95% CI 1.31-2.03), but not after cesarean delivery (RR 0.85, 95% CI 0.73-1.00). INTERPRETATION: Initiation of oxycodone (v. codeine) was not associated with an increased risk of persistent opioid use, except after vaginal delivery.