Severe Maternal Morbidity in Canada: Temporal Trends and Regional Variations, 2003-2016

Trends in maternal ICU admissions at a quaternary centre in Montreal, Canada, and impact of maternal age on critical care outcomes

Background

Advancing maternal age is increasingly prevalent and is associated with severe maternal morbidity often requiring intensive care unit (ICU) admission.

Objectives

To describe maternal ICU admissions at a quaternary care hospital in Montreal, Canada, and evaluate the association between maternal age and composite of: need for invasive interventions, ICU stay > 48 h, or maternal death.

Methods

Chart review of ICU admissions during pregnancy/postpartum (2006-2016); logistic regressions to evaluate the impact of age on outcomes.

Results

With 5.1 ICU admissions per 1000 deliveries, we included 187 women (mean age 32 ± 6.3 years; 20 (10.7%) ≥ 40 years). The composite outcome occurred in 105 (56.2%) patients; there were two maternal deaths. Age ≥ 40 years increased the odds of invasive interventions (OR 4.03; 95% confidence interval [CI] 1.15-14.1) but not of the composite outcome (OR 2.30; 95% CI 0.66-8.02).

Conclusion

Peripartum women aged ≥ 40 years had worse outcomes in ICU, with an increased need for invasive interventions.

Critical Care Services for Pregnant Patients in Ontario: A Province-Wide Survey

Critically ill pregnant patients require advanced critical care support, but access to these services is variable. We surveyed active Ontario obstetric facilities regarding critical care access. Responses were received from 44 of 80 obstetric units (55%), 13 (30%) being rural. Transport to another facility was required by 59% (majority >1 hour transport time), and differences were noted in the availability of specialty support services such as anesthesia and internal/obstetric medicine, as well as radiology and laboratory facilities, and use of massive transfusion protocols. Training in early supportive care of obstetric complications and optimized facility transport are areas for potential improvement.

Outcomes associated with planned place of birth among low-risk pregnancies in Ontario, Canada (2012-2021): A protocol for a population-based propensity score weighted cohort study

BACKGROUND

Evidence suggests that for low-risk pregnancies, planned home births attended by a skilled health professional in settings where such services are well integrated are associated with lower risk of intrapartum interventions and no increase in adverse health outcomes. Monitoring and updating evidence on the safety of planned home births is necessary to inform ongoing clinical and policy decisions.

METHODS

This protocol describes a population-based retrospective cohort study which aims to compare risk of (a) neonatal morbidity and mortality, and (b) maternal outcomes and birth interventions, between people at low obstetrical risk with a planned home birth with a midwife, a planned a hospital birth with a midwife, or a planned hospital birth with a physician. The study population will include Ontario residents who gave birth in Ontario, Canada between April 1, 2012, and March 31, 2021. We will use data collected prospectively in a provincial perinatal data registry. The primary outcome will be severe neonatal morbidity or mortality, a composite binary outcome that includes one or more of the following conditions: stillbirth during the intrapartum period, neonatal death (death of a liveborn infant in the first 28 completed days of life), five-minute Apgar score <4, or infant resuscitation requiring cardiac compressions. We will conduct a stratified analysis with three strata: nulliparous, parous-no previous caesarean birth, and parous-prior caesarean birth. To reduce the impact of selection bias in estimating the effect of planned place of birth on neonatal and maternal outcomes, we will use propensity score (PS) overlap weighting (OW) and modified Poisson regression to conduct multivariate analyses.

Severe maternal morbidity surveillance, temporal trends and regional variation: A population-based cohort study

OBJECTIVE

To quantify temporal trends and regional variation in severe maternal morbidity (SMM) in Sweden.

DESIGN

Cohort study.

POPULATION

Live birth and stillbirth deliveries in Sweden, 1999-2019.

METHODS

Types and subtypes of SMM were identified, based on a standard list (modified for Swedish clinical setting after considering the frequency and validity of each indicator) using diagnoses and procedure codes, among all deliveries at ≥22 weeks of gestation (including complications within 42 days of delivery). Contrasts between regions were quantified using rate ratios (RRs) and 95% confidence intervals (95% CIs). Temporal changes in SMM types and subtypes were described.

MAIN OUTCOME MEASURES

Types and subtypes of SMM.

RESULTS

There were 59 789 SMM cases among 2 212 576 deliveries, corresponding to 270.2 (95% CI 268.1-272.4) per 10 000 deliveries. Composite SMM rates increased from 236.6 per 10 000 deliveries in 1999 to 307.3 per 10 000 deliveries in 2006, before declining to 253.8 per 10 000 deliveries in 2019. Changes in composite SMM corresponded with temporal changes in severe haemorrhage rates, which increased from 94.9 per 10 000 deliveries in 1999 to 169.3 per 10 000 deliveries in 2006, before declining to 111.2 per 10 000 deliveries in 2019. Severe pre-eclampsia, eclampsia and HELLP (haemolysis, elevated liver enzymes and low platelet count) syndrome (103.8 per 10 000 deliveries), severe haemorrhage (133.7 per 10 000 deliveries), sepsis, embolism, disseminated intravascular coagulation, shock and severe mental health disorders were the most common SMM types. Rates of embolism, disseminated intravascular coagulation and shock, acute renal failure, cardiac complications, sepsis and assisted ventilation increased, whereas rates of surgical complications, severe uterine rupture and anaesthesia complications declined.

CONCLUSIONS

The observed spatiotemporal variations in composite SMM and SMM types provide substantive insights and highlight regional priorities for improving maternal health.

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.

Impact of inherited bleeding disorders on maternal bleeding and other pregnancy outcomes: A population-based cohort study

INTRODUCTION

Increasing rate of postpartum haemorrhage (PPH) has been observed between 2003 and 2010 in Canada. Inherited bleeding disorders contribute to the risk of PPH.

AIM

To identify the trend in PPH in the last decade, assess the impact of bleeding disorders on pregnancy outcomes and evaluate their coagulation workup during pregnancy.

METHODS

We conducted a population-based retrospective cohort study using the Alberta Pregnancy Birth Cohort from 2010 to 2018. We included women with von Willebrand disease (VWD) and haemophilia, identified by previously validated algorithm and matched with controls. Logistic regression was used to compute odds of PPH and other pregnancy outcomes.

RESULTS

We identified 311,330 women with a total of 454,400 pregnancies with live births. The rate of PPH did not change significantly from 10.13 per 100 deliveries (95% CI 10.10-10.16) in 2010-10.72 (95% CI 10.69-10.75) in 2018 (p for trend = .35). Women with bleeding disorders were significantly more likely to experience PPH (odds ratio [OR] 2.3; 95% CI 1.5-3.6), antepartum haemorrhage (OR 2.9; 95% CI 1.5-5.9) and red cell transfusion (OR 2.8; 95% CI 1.1-7.0). We observed a nonsignificant rise in the rate of PPH in women with VWD and haemophilia. Only 49.5% pregnancies with bleeding disorders had third trimester coagulation factor levels checked. Higher odds of PPH and antepartum haemorrhage were observed even with factor levels ≥0.50 IU/mL in third trimester.

CONCLUSION

Despite comprehensive care in women with bleeding disorders, they are still at higher risk of adverse pregnancy outcomes compared to population controls.

Postpartum haemorrhage in high-resource settings: Variations in clinical management and future research directions based on a comparative study of national guidelines

OBJECTIVE

To compare guidelines from eight high-income countries on prevention and management of postpartum haemorrhage (PPH), with a particular focus on severe PPH.

DESIGN

Comparative study.

SETTING

High-resource countries.

POPULATION

Women with PPH.

METHODS

Systematic comparison of guidance on PPH from eight high-income countries.

MAIN OUTCOME MEASURES

Definition of PPH, prophylactic management, measurement of blood loss, initial PPH-management, second-line uterotonics, non-pharmacological management, resuscitation/transfusion management, organisation of care, quality/methodological rigour.

CONCLUSIONS

Our study highlights areas where strong evidence is lacking. There is need for a universal definition of (severe) PPH. Consensus is required on how and when to quantify blood loss to identify PPH promptly. Future research may focus on timing and sequence of second-line uterotonics and non-pharmacological interventions and how these impact maternal outcome. Until more data are available, different transfusion strategies will be applied. The use of clear transfusion-protocols are nonetheless recommended to reduce delays in initiation. There is a need for a collaborative effort to develop standardised, evidence-based PPH guidelines.

RESULTS

Definitions of (severe) PPH varied as to the applied cut-off of blood loss and incorporation of clinical parameters. Dose and mode of administration of prophylactic uterotonics and methods of blood loss measurement were heterogeneous. Recommendations on second-line uterotonics differed as to type and dose. Obstetric management diverged particularly regarding procedures for uterine atony. Recommendations on transfusion approaches varied with different thresholds for blood transfusion and supplementation of haemostatic agents. Quality of guidelines varied considerably.

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.

Maternal sepsis in pregnancy and the puerperal periods: a cross-sectional study

Maternal sepsis is a life-threatening condition and ranks among the top five causes of maternal death in pregnancy and the postpartum period. Herein, we conducted a retrospective study on sepsis cases to explain the related risk factors by comparing them with bloodstream infection (BSI) and control maternities. In total, 76 sepsis cases were enrolled, and 31 BSI and 57 maternal cases of the same age but with neither sepsis nor BSI were set as controls. Genital tract infection (GTI) and pneumonia were the two most common infection sources in both sepsis (22 cases, 29% and 29 cases, 38%) and BSI cases (18 cases, 58% and 8 cases, 26%). Urinary tract infection (UTI)/pyelonephritis (9 cases, 12%) and digestive infection cases (11 cases, 14%) only existed in the sepsis group. Significantly different infection sources were discovered between the sepsis-death and sepsis-cure groups. A higher proportion of pneumonia and a lower proportion of GTI cases were present in the sepsis-death group (17 cases, 45% pneumonia and 9 cases, 24% GTI) than in the sepsis-cure group (12 cases, 32% pneumonia and 13 cases, 34% GTI). In addition, although gram-negative bacteria were the dominant infectious microorganisms as previously reported, lower proportion of gram-negative bacteria infectious cases in sepsis (30 cases, 50%) and even lower in sepsis-death group (14 cases, 41%) was shown in this study than previous studies. As expected, significantly greater adverse maternal and fetal outcomes, such as higher maternal mortality (26.3% vs. 0% vs. 0%), higher fetal mortality (42.2% vs. 20.8% vs. 0%), earlier gestational age at delivery (26.4 ± 9.5 vs. 32.3 ± 8.1 vs. 37.7 ± 4.0) and lower newborn weight (1,590 ± 1287.8 vs. 2859.2 ± 966.0 vs. 3214.2 ± 506.4), were observed in the sepsis group. This study offered some potential pathogenesis and mortality risk factors for sepsis, which may inspire the treatment of sepsis in the future.

Severe Maternal Morbidity and Mortality Among Immigrant and Canadian-Born Women Residing Within Low-Income Neighborhoods in Ontario, Canada

IMPORTANCE

Evidence indicates that immigrant women and women residing within low-income neighborhoods experience higher adversity during pregnancy. Little is known about the comparative risk of severe maternal morbidity or mortality (SMM-M) among immigrant vs nonimmigrant women living in low-income areas.

OBJECTIVE

To compare the risk of SMM-M between immigrant and nonimmigrant women residing exclusively within low-income neighborhoods in Ontario, Canada.

DESIGN, SETTING, AND PARTICIPANTS

This population-based cohort study used administrative data for Ontario, Canada, from April 1, 2002, to December 31, 2019. Included were all 414 337 hospital-based singleton live births and stillbirths occurring between 20 and 42 weeks' gestation, solely among women residing in an urban neighborhood of the lowest income quintile; all women were receiving universal health care insurance. Statistical analysis was performed from December 2021 to March 2022.

EXPOSURES

Nonrefugee immigrant status vs nonimmigrant status.

MAIN OUTCOMES AND MEASURES

The primary outcome, SMM-M, was a composite outcome of potentially life-threatening complications or mortality occurring within 42 days of the index birth hospitalization. A secondary outcome was SMM severity, approximated by the number of SMM indicators (0, 1, 2 or ≥3 indicators). Relative risks (RRs), absolute risk differences (ARDs), and odds ratios (ORs) were adjusted for maternal age and parity.

RESULTS

The cohort included 148 085 births to immigrant women (mean [SD] age at index birth, 30.6 [5.2] years) and 266 252 births to nonimmigrant women (mean [SD] age at index birth, 27.9 [5.9] years). Most immigrant women originated from South Asia (52 447 [35.4%]) and the East Asia and Pacific (35 280 [23.8%]) regions. The most frequent SMM indicators were postpartum hemorrhage with red blood cell transfusion, intensive care unit admission, and puerperal sepsis. The rate of SMM-M was lower among immigrant women (2459 of 148 085 [16.6 per 1000 births]) than nonimmigrant women (4563 of 266 252 [17.1 per 1000 births]), equivalent to an adjusted RR of 0.92 (95% CI, 0.88-0.97) and an adjusted ARD of -1.5 per 1000 births (95% CI, -2.3 to -0.7). Comparing immigrant vs nonimmigrant women, the adjusted OR of having 1 SMM indicator was 0.92 (95% CI, 0.87-0.98), the adjusted OR of having 2 indicators was 0.86 (95% CI, 0.76-0.98), and the adjusted OR of having 3 or more indicators was 1.02 (95% CI, 0.87-1.19).

CONCLUSIONS AND RELEVANCE

This study suggests that, among universally insured women residing in low-income urban areas, immigrant women have a slightly lower associated risk of SMM-M than their nonimmigrant counterparts. Efforts aimed at improving pregnancy care should focus on all women residing in low-income neighborhoods.

Black-White disparity in severe cardiovascular maternal morbidity: A systematic review and meta-analysis

BACKGROUND

To synthesize existing evidence on Black-White disparities in the prevalence of severe cardiovascular maternal morbidity.

METHODS

We searched MEDLINE, EMBASE, and CINAHL for observational studies published before July 31, 2021 that compared the risk of severe cardiovascular maternal morbidity between Black and White women. The outcome was severe cardiovascular maternal morbidity, including acute myocardial infarction, peripartum cardiomyopathy, and stroke during pregnancy, delivery, or postpartum. We extracted relevant information including adjusted and unadjusted effect estimates. We used random-effects models to estimate the pooled association between race and severe cardiovascular maternal morbidity, presented as odds ratios with 95% confidence intervals for the comparison of Black women relative to White women.

RESULTS

We included 18 studies that met the eligibility criteria for systematic review and meta-analysis. All studies were conducted in the United States and included a total of 7,656,876 Black women and 26,412,600 White women. Compared with White women, Black women had an increased risk of any severe cardiovascular maternal morbidity (adjusted odds ratio, 1.90; 95% confidence interval, 1.54-2.33). Black women were at risk of acute myocardial infarction (adjusted odds ratio, 1.38; 95% confidence interval, 1.14-1.68), peripartum cardiomyopathy (adjusted odds ratio, 1.71; 95% confidence interval, 1.51-1.94), and stroke (adjusted odds ratio, 2.13; 95% confidence interval, 1.39-3.26).

CONCLUSIONS

Black women have a considerably higher risk of severe cardiovascular maternal morbidity than White women, including acute myocardial infarction, peripartum cardiomyopathy, and stroke. Reducing inequality in adverse cardiovascular outcomes of pregnancy between Black and White women should be prioritized.

Timing of neonatal mortality and severe morbidity during the postnatal period: a systematic review

OBJECTIVE

The objective of this review was to determine the timing of overall and cause-specific neonatal mortality and severe morbidity during the postnatal period (1-28 days).

INTRODUCTION

Despite significant focus on improving neonatal outcomes, many newborns continue to die or experience adverse health outcomes. While evidence on neonatal mortality and severe morbidity rates and causes are regularly updated, less is known on the specific timing of when they occur in the neonatal period.

INCLUSION CRITERIA

This review considered studies that reported on neonatal mortality daily in the first week; weekly in the first month; or day 1, days 2-7, and days 8-28. It also considered studies that reported on timing of severe neonatal morbidity. Studies that reported solely on preterm or high-risk infants were excluded, as these infants require specialized care. Due to the available evidence, mixed samples were included (eg, both preterm and full-term infants), reflecting a neonatal population that may include both low-risk and high-risk infants.

METHODS

MEDLINE, Embase, Web of Science, and CINAHL were searched for published studies on December 20, 2019, and updated on May 10, 2021. Critical appraisal was undertaken by 2 independent reviewers using standardized critical appraisal instruments from JBI. Quantitative data were extracted from included studies independently by 2 reviewers using a study-specific data extraction form. All conflicts were resolved through consensus or discussion with a third reviewer. Where possible, quantitative data were pooled in statistical meta-analysis. Where statistical pooling was not possible, findings were reported narratively.

RESULTS

A total of 51 studies from 36 articles reported on relevant outcomes. Of the 48 studies that reported on timing of mortality, there were 6,760,731 live births and 47,551 neonatal deaths with timing known. Of the 34 studies that reported daily deaths in the first week, the highest proportion of deaths occurred on the first day (first 24 hours, 38.8%), followed by day 2 (24-48 hours, 12.3%). Considering weekly mortality within the first month (n = 16 studies), the first week had the highest mortality (71.7%). Based on data from 46 studies, the highest proportion of deaths occurred on day 1 (39.5%), followed closely by days 2-7 (36.8%), with the remainder occurring between days 8 and 28 (23.0%). In terms of causes, birth asphyxia accounted for the highest proportion of deaths on day 1 (68.1%), severe infection between days 2 and 7 (48.1%), and diarrhea between days 8 and 28 (62.7%). Due to heterogeneity, neonatal morbidity data were described narratively. The mean critical appraisal score of all studies was 84% (SD = 16%).

CONCLUSION

Newborns experience high mortality throughout the entire postnatal period, with the highest mortality rate in the first week, particularly on the first day. Ensuring regular high-quality postnatal visits, particularly within the first week after birth, is paramount to reduce neonatal mortality and severe morbidity.

Development and internal validation of a model to predict type 2 diabetic complications after gestational diabetes

Gestational diabetes mellitus (GDM) increases the risk of early-onset type 2 diabetes, which further exacerbates the risk of developing diabetic complications such as kidney, circulatory, and neurological complications. Yet, existing models have solely focused on the prediction of type 2 diabetes, and not of its complications, which are arguably the most clinically relevant outcomes. Our aim was to develop a prediction model for type 2 diabetic complications in patients with GDM. Using provincial administrative data from Quebec, Canada, we developed a model to predict type 2 diabetic complications within 10 years among 90,143 women with GDM. The model was internally validated and assessed for discrimination, calibration, and risk stratification accuracy. The incidence of diabetic complications was 3.8 (95% confidence interval (CI) 3.4-4.3) per 10,000 person-years. The final prediction model included maternal age, socioeconomic deprivation, substance use disorder, gestational age at delivery, severe maternal morbidity, previous pregnancy complications, and hypertensive disorders of pregnancy. The model had good discrimination [area under the curve (AUROC) 0.72 (95% CI 0.69-0.74)] and calibration (slope ≥ 0.9) to predict diabetic complications. In the highest category of the risk stratification table, the positive likelihood ratio was 8.68 (95% CI 4.14-18.23), thereby showing a moderate ability to identify women at highest risk of developing type 2 diabetic complications. Our model predicts the risk of type 2 diabetic complications with moderate accuracy and, once externally validated, may prove to be a useful tool in the management of women after GDM.

Severe maternal morbidity and maternal mortality associated with assisted reproductive technology

OBJECTIVE

To assess the association between use of assisted reproductive technologies (ART) and severe maternal morbidity and maternal mortality (SMM).

METHODS

We carried out a cohort study that included all hospital deliveries at ≥20 weeks gestation in Canada (excluding Québec) between April 2009 and March 2018. Outcomes of interest included composite SMM and SMM types (e.g., severe preeclampsia, HELLP syndrome, and eclampsia; severe hemorrhage; acute renal failure). Multivariable regression was used to estimate crude and adjusted rate ratios (RR and aRR) and 95% confidence intervals (CI).

RESULTS

The study included 2 535 056 women, of whom 72 023 (2.8%) delivered following the use of ART. The composite SMM rate for women who used ART was 34.7 per 1000 deliveries (95% CI 33.0-36.0) versus 11.5 per 1000 deliveries (95% CI 11.4-11.6) for women who did not use ART (RR 3.01; 95% CI 2.89-3.14). ART use was associated with SMM types such as severe preeclampsia, HELLP syndrome, and eclampsia (RR 3.50; 95% CI 3.27-3.73), severe hemorrhage (RR 3.58, 95% CI 3.27-3.92), and acute renal failure (RR 6.79; 95% CI 5.78-7.98). Associations between ART and composite SMM were attenuated but remained elevated after adjusting for maternal characteristics (aRR 2.34; 95% CI 2.24-2.45). Women who used ART and had a multi-fetal pregnancy had a 4.7 times higher rate of composite SMM compared with women who did not use ART and delivered singletons.

CONCLUSION

Women who deliver following the use of ART have increased risks of SMM and require counselling that includes mention of the lower risks of SMM associated with ART-conceived singleton pregnancy.

Trends in the Incidence and Risk Factors of Pregnancy-Associated Stroke

Pregnancy is a female-specific risk factor for stroke. Although pregnancy-associated stroke (PAS) is a rare event, PAS leads to considerable maternal mortality and morbidity. It is estimated that 7.7–15% of all maternal deaths worldwide are caused by stroke and 30–50% of surviving women are left with persistent neurological deficits. During last decade, several studies have reported an increasing incidence of PAS. The objective of this review is to summarize studies on time trends of PAS in relation to trends in the prevalence of stroke risk factors in pregnant women. Seven retrospective national healthcare register-based cohort studies from the US, Canada, UK, Sweden, and Finland were identified. Five studies from the US, Canada, and Finland reported an increasing trend of PAS. Potential biases include more sensitive diagnostics and improved stroke awareness among pregnant women and professionals toward the end of the study period. However, the concurrent increase in the prevalence of several stroke risk factors among pregnant women, particularly advanced age, hypertensive disorders of pregnancy, diabetes, and obesity, indicate that the findings are likely robust and should be considered seriously. To reduce stroke in pregnancy, increased awareness among all medical specialties and pregnant women on the importance of risk-factor management during pregnancy and stroke symptoms is necessary. Important preventive measures include counseling for smoking cessation and substance abuse, treatment of hypertensive disorders of pregnancy, use of aspirin in women at high risk for developing preeclampsia, and antithrombotic medication and pregnancy surveillance for women with high-risk conditions. Epidemiological data from countries with a high risk-factor burden are largely missing. National and international registries and prospective studies are needed to increase knowledge on the mechanisms, risk factors, management, and future implications for the health of women who experience this rare but devastating complication of pregnancy.

Preeclampsia and Severe Maternal Morbidity During the COVID-19 Pandemic: A Population-Based Cohort Study in Ontario, Canada

Objective

Significant changes to the delivery of obstetrical care that occurred with the onset of the COVID-19 pandemic may be associated with higher risks of adverse maternal outcomes. We evaluated preeclampsia/HELLP (hemolysis, elevated liver enzymes and low platelets) syndrome and composite severe maternal morbidity (SMM) among pregnant people who gave birth during the COVID-19 pandemic and compared these data with those of people who gave birth before the pandemic in Ontario, Canada.

Methods

This was a population-based, retrospective cohort study using linked administrative data sets from ICES. Data on pregnant people at ≥20 weeks gestation who gave birth between March 15, 2020, and September 30, 2021, were compared with those of pregnant people who gave birth within the same date range for the years 2015–2019. We used multivariable logistic regression to assess the effect of the pandemic period on the odds of preeclampsia/HELLP syndrome and composite SMM, adjusting for maternal baseline characteristics and comorbidities.

Results

There were no differences between the study periods in the adjusted odds ratios (aORs) for preeclampsia/HELLP syndrome among primiparous (aOR 1.00; 95% CI 0.91–1.11) and multiparous (aOR 0.94; 95% CI 0.81–1.09) patients and no differences for composite SMM (primiparous, aOR 1.00; 95% CI 0.95–1.05; multiparous, aOR 1.01; 95% CI 0.95–1.08).

Conclusion

Adverse maternal outcomes were not higher among pregnant people who gave birth during the first 18 months of the COVID-19 pandemic in Ontario, Canada, when compared with those who gave birth before the pandemic.

Feasibility of establishing a Canadian Obstetric Survey System (CanOSS) for severe maternal morbidity: a study protocol

INTRODUCTION

Severe maternal morbidity (SMM)-an unexpected pregnancy-associated maternal outcome resulting in severe illness, prolonged hospitalisation or long-term disability-is recognised by many, as the preferred indicator of the quality of maternity care, especially in high-income countries. Obtaining comprehensive details on events and circumstances leading to SMM, obtained through maternity units, could complement data from large epidemiological studies and enable targeted interventions to improve maternal health. The aim of this study is to assess the feasibility of gathering such data from maternity units across Canadian provinces and territories, with the goal of establishing a national obstetric survey system for SMM in Canada.

METHODS AND ANALYSIS

We propose a sequential explanatory mixed-methods study. We will first distribute a cross-sectional survey to leads of all maternity units across Canada to gather information on (1) Whether the unit has a system for reviewing SMM and the nature and format of this system, (2) Willingness to share anonymised data on SMM by direct entry using a web-based platform and (3) Respondents' perception on the definition and leading causes of SMM at a local level. This will be followed by semistructured interviews with respondent groups defined a priori, to identify barriers and facilitators for data sharing. We will perform an integrated analysis to determine feasibility outcomes, a narrative description of barriers and facilitators for data-sharing and resource implications for data acquisition on an annual basis, and variations in top-5 causes of SMM.

ETHICS AND DISSEMINATION

The study has been approved by the Mount Sinai and Hamilton Integrated Research Ethics Boards. The study findings will be presented at annual scientific meetings of the Society of Obstetricians and Gynaecologists of Canada, North American Society of Obstetric Medicine, and International Network of Obstetric Survey Systems and published in an open-access peer-reviewed Obstetrics and Gynaecology or General Internal Medicine journal.

Timing of maternal mortality and severe morbidity during the postpartum period

Objective:

The objective of this review was to determine the timing of overall and cause-specific maternal mortality and severe morbidity during the postpartum period.

Introduction:

Many women continue to die or experience adverse health outcomes in the postpartum period; however, limited work has explored the timing of when women die or present complications during this period globally.

Inclusion criteria:

This review considered studies that reported on women after birth up to 6 weeks postpartum and included data on mortality and/or morbidity on the first day, days 2–7, and days 8–42. Studies that reported solely on high-risk women (eg, those with antenatal or intrapartum complications) were excluded, but mixed population samples were included (eg, low-risk and high-risk women).

Methods:

MEDLINE, Embase, Web of Science, and CINAHL were searched for published studies on December 20, 2019, and searches were updated on May 11, 2021. Critical appraisal was undertaken by 2 independent reviewers using standardized critical appraisal instruments from JBI. Quantitative data were extracted from included studies independently by at least 2 reviewers using a study-specific data extraction form. Quantitative data were pooled, where possible. Identified studies were used to obtain the summary estimate (proportion) for each time point. Maternal mortality was calculated as the maternal deaths during a given period over the total number of maternal deaths known during the postpartum period. For cause-specific analysis, number of deaths due to a specific cause was the numerator, while the total number of women who died due to the same cause in that period was the denominator. Random effects models were run to pool incidence proportion for relative risk of overall maternal deaths. Subgroup analysis was conducted according to country income classification and by date (ie, data collection before or after 2010). Where statistical pooling was not possible, the findings were reported narratively.

Results:

A total of 32 studies reported on maternal outcomes from 17 reports, all reporting on mixed populations. Most maternal deaths occurred on the first day (48.9%), with 24.5% of deaths occurring between days 2 and 7, and 24.9% occurring between days 8 and 42. Maternal mortality due to postpartum hemorrhage and embolism occurred predominantly on the first day (79.1% and 58.2%, respectively). Most deaths due to postpartum eclampsia and hypertensive disorders occurred within the first week (44.3% on day 1 and 37.1% on days 2–7). Most deaths due to infection occurred between days 8 and 42 (61.3%). Due to heterogeneity, maternal morbidity data are described narratively, with morbidity predominantly occurring within the first 2 weeks. The mean critical appraisal score across all included studies was 85.9% (standard deviation = 13.6%).

Conclusion:

Women experience mortality throughout the entire postpartum period, with the highest mortality rate on the first day. Access to high-quality care during the postpartum period, including enhanced frequency and quality of postpartum assessments during the first 42 days after birth, is essential to improving maternal outcomes and to continue reducing maternal mortality and morbidity worldwide.

Systematic review registration number:

PROSPERO CRD42020187341

Severe Maternal Morbidity and Long-Term Risk of Cardiovascular Hospitalization

BACKGROUND

Severe maternal morbidity is rising, yet the association with cardiovascular disease is not clear. We examined the risk of cardiovascular hospitalization up to 3 decades after having a pregnancy complicated by severe maternal morbidity.

METHODS

We analyzed a longitudinal cohort of 1 336 846 women who were pregnant between 1989 and 2019 in Quebec, Canada. The main exposure measure was severe maternal morbidity in any pregnancy, including severe preeclampsia, acute renal failure, sepsis, and other life-threatening conditions. Using time-varying Cox regression models, we compared the adjusted risk of hospitalization for cardiovascular disease up to 3 decades after pregnancy for women with severe maternal morbidity relative to women without severe morbidity.

RESULTS

Five percent of women had severe maternal morbidity. Overall, there were 68 287 cardiovascular hospitalizations during 21 725 672 person-years of follow-up in the cohort. Compared with no morbidity, women with any severe morbidity had a greater risk of cardiovascular hospitalization (hazard ratio [HR], 1.77 [95% CI, 1.72-1.82]). The association was the greatest within the first year of delivery (HR, 4.42 [95% CI, 3.77-5.19]) but persisted beyond 15 years (HR, 1.44 [95% CI, 1.37-1.51]). Having a cardiac complication (HR, 5.37 [95% CI, 4.65-6.20]), cerebrovascular accident (HR, 3.82 [95% CI, 2.94-4.96]), or acute renal failure (HR, 2.60 [95% CI, 2.15-3.14]) during pregnancy was strongly associated with future cardiovascular hospitalization.

CONCLUSIONS

Women with severe maternal morbidity have a greater risk of cardiovascular disease after pregnancy, both in the short and long term. These women may benefit from active surveillance for cardiovascular disease.

Obstetrical and Perinatal Outcomes in Female Survivors of Childhood and Adolescent Cancer: A Population-Based Cohort Study

BACKGROUND

The likelihood of pregnancy and risk of obstetrical or perinatal complications is inadequately documented in female survivors of pediatric cancer.

METHODS

We assembled a population-based cohort of female survivors of cancer diagnosed at age 21 years and younger in Ontario, Canada, between 1985 and 2012. Survivors were matched 1:5 to women without prior cancer. Multivariable Cox proportional hazards and modified Poisson models assessed the likelihood of a recognized pregnancy and perinatal and maternal complications.

RESULTS

A total of 4062 survivors were matched to 20 308 comparisons. Median (interquartile range) age was 11 (4-15) years at cancer diagnosis and 25 (19-31) years at follow-up. By age 30 years, the cumulative incidence of achieving a recognized pregnancy was 22.3% (95% confidence interval [CI] = 20.7% to 23.9%) among survivors vs 26.6% (95% CI = 25.6% to 27.3%) among comparisons (hazard ratio = 0.80, 95% CI = 0.75 to 0.86). A lower likelihood of pregnancy was associated with a brain tumor, alkylator chemotherapy, cranial radiation, and hematopoietic stem cell transplantation. Pregnant survivors were as likely as cancer-free women to carry a pregnancy >20 weeks (relative risk [RR] = 1.01, 95% CI = 0.98 to 1.04). Survivors had a higher relative risk of severe maternal morbidity (RR = 2.31, 95% CI = 1.59 to 3.37), cardiac morbidity (RR = 4.18, 95% CI = 1.89 to 9.24), and preterm birth (RR = 1.57, 95% CI = 1.29 to 1.92). Preterm birth was more likely in survivors treated with hematopoietic stem cell transplantation (allogenic: RR = 8.37, 95% CI = 4.83 to 14.48; autologous: RR = 3.72, 95% CI = 1.66 to 8.35).

CONCLUSIONS

Survivors of childhood or adolescent cancer are less likely to achieve a pregnancy and, once pregnant, are at higher risk for severe maternal morbidity and preterm birth.

Measuring State-Level Racial Inequity in Severe Maternal Morbidity in the Medicaid Population

OBJECTIVE

Severe maternal morbidity represents a "near miss" mortality and is an important measure of quality and safety. Racial inequity in maternal morbidity is stark and the reasons for this disparity are poorly understood. We aimed to identify states achieving racial equity in maternal morbidity in order to identify policies that may promote racial equity.

METHODS

We analyzed Medicaid deliveries from 2008 to 2009 in a sample that included 28 states and the District of Columbia. This dataset included approximately 80% of all Medicaid enrollees and 90% of minority Medicaid enrollees in the US. We determined the Non-Hispanic Black/Non-Hispanic white SMMI rate ratio for each state and categorized the states into groups by rate ratio. We described demographic features of both the general population and study population for these groups of states.

RESULTS

In a sample that included a total of 1,489,134 births, we found that no state/district is achieving equity in severe maternal morbidity. The severe maternal morbidity rate is higher for Non-Hispanic Black than Non-Hispanic white patients in every state included. With a rate ratio ranging from 1.14 to 2.66, there are varying degrees of inequity. States in the group with the most equitable maternal morbidity rates had less inequity across racial subgroups with respect to educational attainment and poverty.

CONCLUSIONS

Identifying geographic areas with varying degrees of inequity may be key to identifying policies to promote equity. Socioecological disparities and inadequate access to care may be factors in racial inequity in maternal morbidity.

Incidence and risk factors for severe preeclampsia, hemolysis, elevated liver enzymes, and low platelet count syndrome, and eclampsia at preterm and term gestation: a population-based study

BACKGROUND

The majority of previous studies on severe preeclampsia, eclampsia, and hemolysis, elevated liver enzymes, and low platelet count syndrome were hospital-based or included a relatively small number of women. Large, population-based studies examining gestational age-specific incidence patterns and risk factors for these severe pregnancy complications are lacking.

OBJECTIVE

This study aimed to assess the gestational age-specific incidence rates and risk factors for severe preeclampsia, hemolysis, elevated liver enzymes, and low platelet count syndrome, and eclampsia.

STUDY DESIGN

We carried out a retrospective, population-based cohort study that included all women with a singleton hospital birth in Canada (excluding Quebec) from 2012 to 2016 (N=1,078,323). Data on the primary outcomes (ie, severe preeclampsia, hemolysis, elevated liver enzymes, and low platelet count syndrome, and eclampsia) were obtained from delivery hospitalization records abstracted by the Canadian Institute for Health Information. A Cox regression was used to assess independent risk factors (eg, maternal age and chronic comorbidity) for each primary outcome and to assess differences in the effects at preterm vs term gestation (<37 vs ≥37 weeks).

RESULTS

The rates of severe preeclampsia (n=2533), hemolysis, elevated liver enzymes, and low platelet count syndrome (n=2663), and eclampsia (n=465) were 2.35, 2.47, and 0.43 per 1000 singleton pregnancies, respectively. The cumulative incidence of term-onset severe preeclampsia was lower than that of preterm-onset severe preeclampsia (0.87 vs 1.54 per 1000; rate ratio, 0.57; 95% confidence intervals, 0.53-0.62), the rates of hemolysis, elevated liver enzymes, and low platelet count syndrome were similar (1.32 vs 1.23 per 1000; rate ratio, 0.93; 95% confidence interval, 0.86-1.00), and the preterm-onset eclampsia rate was lower than the term-onset rate (0.12 vs 0.33 per 1000; rate ratio, 2.64; 95% confidence interval, 2.16-3.23). For each primary outcome, chronic comorbidity and congenital anomalies were stronger risk factors for preterm- vs term-onset disease. Younger mothers (aged <25 years) were at higher risk for severe preeclampsia at term and for eclampsia at all gestational ages, whereas older mothers (aged ≥35 years) had elevated risks for severe preeclampsia and hemolysis, elevated liver enzymes, and low platelet count syndrome. Regardless of gestational age, nulliparity was a risk factor for all outcomes, whereas socioeconomic status was inversely associated with severe preeclampsia.

CONCLUSION

The risk for severe preeclampsia declined at term, eclampsia risk increased at term, and hemolysis, elevated liver enzymes, and low platelet count syndrome risk was similar for preterm and term gestation. Young maternal age was associated with an increased risk for eclampsia and term-onset severe preeclampsia. Prepregnancy comorbidity and fetal congenital anomalies were more strongly associated with severe preeclampsia, hemolysis, elevated liver enzymes, and low platelet count syndrome, and eclampsia at preterm gestation.

Neighbourhood material deprivation and severe maternal morbidity: a population-based cohort study in Ontario, Canada

OBJECTIVES

Rates of age-associated severe maternal morbidity (SMM) have increased in Canada, and an association with neighbourhood income is well established. Our aim was to examine SMM trends according to neighbourhood material deprivation quintile, and to assess whether neighbourhood deprivation effects are moderated by maternal age.

DESIGN, SETTING AND PARTICIPANTS

A population-based retrospective cohort study using linked administrative databases in Ontario, Canada. We included primiparous women with a live birth or stillbirth at ≥20 weeks' gestational age.

PRIMARY OUTCOME

SMM from pregnancy onset to 42 days postpartum. We calculated SMM rate differences (RD) and rate ratios (RR) by neighbourhood material deprivation quintile for each of four 4-year cohorts from 1 April 2002 to 31 March 2018. Log-binomial multivariable regression adjusted for maternal age, demographic and pregnancy-related variables.

RESULTS

There were 1 048 845 primiparous births during the study period. The overall rate of SMM was 18.0 per 1000 births. SMM rates were elevated for women living in areas with high material deprivation. In the final 4-year cohort, the RD between women living in high vs low deprivation neighbourhoods was 3.91 SMM cases per 1000 births (95% CI: 2.12 to 5.70). This was higher than the difference observed during the first 4-year cohort (RD 2.09, 95% CI: 0.62 to 3.56). SMM remained associated with neighbourhood material deprivation following multivariable adjustment in the pooled sample (RR 1.16, 95% CI: 1.11 to 1.21). There was no evidence of interaction with maternal age.

CONCLUSION

SMM rate increases were more pronounced for primiparous women living in neighbourhoods with high material deprivation compared with those living in low deprivation areas. This raises concerns of a widening social gap in maternal health disparities and highlights an opportunity to focus risk reduction efforts toward disadvantaged women during pregnancy and postpartum.

Anesthesia-related adverse events in obstetric patients: a population-based study in Canada

BACKGROUND

Anesthesia-related complications in obstetric patients could be catastrophic and impact the lives of both the parturient and the neonate. The objective of this study was to determine the frequency, temporal trend, and risk factors of anesthesia-related adverse events during hospitalization for delivery in Canada.

METHODS

This retrospective population-based study utilized the hospitalization database of the Canadian Institute for Health Information for all parturients (gestation ≥ 20 weeks) in Canada (except Quebec) hospitalized for childbirth from April 2004 to March 2017. Complications were identified by the enhanced Canadian version of the tenth revision of the International Statistical Classification of Diseases and Related Health Problems codes. Data were summarized with descriptive statistics. Associations between hospitalizations with an anesthesia-related adverse event and patient characteristics, delivery method, and modality of anesthesia were assessed using multivariate logistic regression.

RESULTS

Among 2,601,034 hospitalizations (3,194,875 interventions), 8,361 anesthesia-related adverse events occurred over a 13-year period (262 per 100,000 interventions; 95% confidence interval [CI], 256 to 267), with a significant decline over time (P < 0.001). These were two-fold and seven-fold higher per 100,000 interventions with general (488; 95% CI, 438 to 542) and general plus neuraxial (1,476; 95% CI, 1,284 to 1,689) anesthesia compared with neuraxial anesthesia alone (225; 95% CI, 219 to 230). Serious adverse events constituted 9% of all adverse events. The most common adverse event was spinal and epidural anesthesia-induced headache (6,908/8,361; 83%); the overall rate of failed or difficult intubations was low (201/8,361; 2%). Anesthesia-related events were more likely in those who had a Cesarean delivery compared with vaginal delivery (odds ratio [OR], 1.12; 95% CI, 1.06 to 1.18) and general anesthesia compared with neuraxial anesthesia (OR, 1.71; 95% CI, 1.53 to 1.93). Noteworthy associations were found between any anesthesia-related adverse events and cardiomyopathy (OR, 8.34; 95% CI, 2.59 to 26.83), eclampsia (OR, 3.11; 95% CI, 1.95 to 4.97), and obstructive sleep apnea (OR, 1.91; 95% CI, 1.66 to 2.19).

CONCLUSION

The incidence of anesthesia-related adverse events in obstetric patients in Canada is low and declining. High vigilance is required in parturients undergoing Cesarean delivery, receiving general anesthesia, and those with pre-existing medical conditions.

Severe Maternal Morbidity and Risk of Mortality Beyond the Postpartum Period

OBJECTIVE

To examine long-term risks of mortality after a pregnancy complicated by severe maternal morbidity.

METHODS

We analyzed a longitudinal cohort of 1,229,306 women who delivered in the province of Quebec, Canada from 1989 through 2016. Severe maternal morbidity included conditions such as cerebrovascular accidents, acute renal failure, severe preeclampsia, and other life-threatening complications. The outcome was in-hospital mortality after the last pregnancy, categorized as postpartum (42 days or fewer after delivery) and long-term (43 days to 29 years after delivery). We estimated hazard ratios (HRs) ofr mortality with 95% CI for severe maternal morbidity compared with no severe morbidity, using Cox regression models adjusted for maternal characteristics.

RESULTS

Severe maternal morbidity occurred in 2.9% of women. The mortality rate associated with severe maternal morbidity was 0.86 per 1,000 person-years compared with 0.41 per 1,000 person-years for no morbidity. Compared with no morbidity, severe maternal morbidity was associated with two times the rate of death any time after delivery (95% CI 1.81-2.20). Severe cardiac complications (HR 7.00, 85% CI 4.94-9.91), acute renal failure (HR 4.35, 95% CI 2.66-7.10), and cerebrovascular accidents (HR 4.03, 95% CI 2.17-7.48) were the leading morbidities associated with mortality after 42 days.

CONCLUSION

Women who experience severe maternal morbidity have an accelerated risk of mortality beyond the postpartum period compared with women who do not experience severe morbidity. More intensive clinical follow-up may be merited for women with serious pregnancy complications.

Development and Internal Validation of a Model Predicting Premature Cardiovascular Disease Among Women With Hypertensive Disorders of Pregnancy: A Population-Based Study in Quebec, Canada

Background

Hypertensive disorders of pregnancy (HDP) are associated with an increased risk of premature cardiovascular disease (CVD), but existing cardiovascular prediction models do not adequately capture risks in young women. We developed a model to predict the 10‐year risk of premature CVD and mortality among women who have HDP.

Methods and Results

Using a population‐based cohort of women with HDP who delivered between April 1989 and March 2017 in Quebec, Canada, we developed a 10‐year CVD risk model using Cox proportional hazards regression. Women aged 18 to 45 years were followed from their first HDP‐complicated delivery until March 2018. We assessed performance of the model based on discrimination, calibration, and risk stratification ability. Internal validity was assessed using the bootstrap method. The cohort included 95 537 women who contributed 1 401 084 person‐years follow‐up. In total, 4024 (4.2%) of women were hospitalized for CVD, of which 1585 events (1.6%) occurred within 10 years of follow‐up. The final model had modest discriminatory performance (area under the receiver operating characteristic curve, 0.66; 95% CI, 0.65–0.67) and good calibration with slope of 0.95 and intercept of −0.19. There was moderate classification accuracy (likelihood ratio+: 5.90; 95% CI, 5.01–6.95) in the highest‐risk group upon risk stratification.

Conclusions

Overall, our model had modest performance in predicting the 10‐year risk of premature CVD for women with HDP. We recommend the addition of clinical variables, and external validation, before consideration for clinical use.

Severe Maternal Morbidity and Infant Mortality in Canada

BACKGROUND

Severe maternal morbidity (SMM) comprises an array of conditions and procedures denoting an acutely life-threatening pregnancy-related condition. SMM may further compromise fetal well-being. Empirical data are lacking about the relation between SMM and infant mortality.

METHODS

This population-based cohort study included 1 892 857 singleton births between 2002 and 2017 in Ontario, Canada, within a universal health care system. The exposure was SMM as an overall construct arising from 23 weeks' gestation up to 42 days after the index delivery. The primary outcome was infant mortality from birth to 365 days. Multivariable modified Poisson regression generated relative risks and 95% confidence intervals (CIs), adjusted for maternal age, income, rurality, world region of origin, diabetes mellitus, and chronic hypertension.

RESULTS

Infant mortality occurred among 174 of 19 587 live births with SMM (8.9 per 1000) vs 5289 of 1 865 791 live births without SMM (2.8 per 1000) (an adjusted relative risk of 2.93 [95% CI 2.51-3.41]). Of 19 587 pregnancies with SMM, 4523 (23.1%) had sepsis. Relative to births without SMM, the adjusted odds ratio for infant death from sepsis was 1.95 (95% CI 1.10-3.45) if SMM occurred without maternal sepsis and 6.36 (95% CI 3.50-11.55) if SMM included sepsis.

CONCLUSIONS

SMM confers a higher risk of infant death. There is also coupling tendency (concurrent event of interest) between SMM with sepsis and infant death from sepsis. Identification of preventable SMM indicators, as well as the development of strategies to limit their onset or progression, may reduce infant mortality.

Database Autopsy: An Efficient and Effective Confidential Enquiry into Maternal Deaths in Canada

BACKGROUND

Maternal death surveillance in Canada relies on hospitalization data, which lacks information on the underlying cause of death. We developed a method for identifying underlying causes of maternal death, and quantified the frequency of maternal death by cause.

METHODS

We used data from the Discharge Abstract Database for fiscal years 2013 to 2017 to identify women who died in Canadian hospitals (excluding Quebec) while pregnant or within 1 year of the end of pregnancy. A sequential narrative based on hospital admission(s) during and after pregnancy was constituted and reviewed to assign the underlying cause of death (based on the World Health Organization's framework). Maternal deaths (i.e., while pregnant or within 42 days after the end of pregnancy) and late maternal deaths (i.e., more than 42 days to a year after the end of pregnancy) were examined separately.

RESULTS

We identified 85 maternal deaths. Direct obstetric causes included 8 deaths (9%) related to complications of spontaneous or induced abortion; 9 (11%), to hypertensive disorders of pregnancy; 15 (18%), to obstetric hemorrhage; 11 (13%), to pregnancy-related infection; 16 (19%), to other obstetric complications; and <5 (<6%), to complications of management. There were 21 (25%) maternal deaths with indirect obstetric causes, and <5 (<6%) with undetermined causes. Of 120 late maternal deaths, 16 (13%) had direct obstetric causes, among them, 9 deaths by suicide (56%). One hundred late maternal deaths (83%) had indirect obstetric causes; and <5 (<4%) had undetermined causes.

CONCLUSIONS

The majority of maternal deaths in Canada have direct obstetric causes, whereas most late maternal deaths have indirect obstetric causes. Suicide is an important direct cause of late maternal death.

Risk of severe maternal morbidity or death in relation to elevated hemoglobin A1c preconception, and in early pregnancy: A population-based cohort study

BACKGROUND

The relation between prepregnancy average glucose concentration and a woman's risk of severe maternal morbidity (SMM) is unknown. The current study evaluated whether an elevated preconception hemoglobin A1c (A1c) is associated with SMM or maternal death among women with and without known prepregnancy diabetes mellitus (DM).

METHODS AND FINDINGS

A population-based cohort study was completed in Ontario, Canada, where there is universal healthcare. The main cohort included 31,225 women aged 16-50 years with a hospital live birth or stillbirth from 2007 to 2015, and who had an A1c measured within 90 days before conception, including 28,075 women (90%) without known prepregnancy DM. The main outcome was SMM or maternal mortality from 23 weeks' gestation up to 42 days postpartum. Relative risks (RRs) were generated using modified Poisson regression, adjusting for the main covariates of maternal age, multifetal pregnancy, world region of origin, and tobacco/drug dependence. The mean maternal age was 31.1 years. Overall, SMM or death arose among 682 births (2.2%). The RR of SMM or death was 1.16 (95% CI 1.14-1.19; p < 0.001) per 0.5% increase in A1c and 1.16 (95% CI 1.13-1.18; p < 0.001) after adjusting for the main covariates. The adjusted relative risk (aRR) was increased among those with (1.11, 95% CI 1.07-1.14; p < 0.001) and without (1.15, 95% CI 1.02-1.29; p < 0.001) known prepregnancy diabetes, and upon further adjusting for body mass index (BMI) (1.15, 95% CI 1.11-1.20; p < 0.001), or chronic hypertension and prepregnancy serum creatinine (1.11, 95% CI 1.04-1.18; p = 0.002). The aRR of SMM or death was 1.31 (95% CI 1.06-1.62; p = 0.01) in those with a preconception A1c of 5.8%-6.4%, and 2.84 (95% CI 2.31-3.49; p < 0.001) at an A1c > 6.4%, each relative to an A1c < 5.8%. Among those without previously recognized prepregnancy diabetes and whose A1c was >6.4%, the aRR of SMM or death was 3.25 (95% CI 1.76-6.00; p < 0.001). Study limitations include that selection bias may have incorporated less healthy women tested for A1c, and BMI was unknown for many women.

CONCLUSIONS

Our findings indicate that women with an elevated A1c preconception may be at higher risk of SMM or death in pregnancy or postpartum, including those without known prepregnancy DM.

Pregnancy outcomes in women with anorexia nervosa

OBJECTIVE

Birth outcomes of women with anorexia nervosa are poorly understood. We hypothesized that hospitalization for anorexia nervosa before or during pregnancy is associated with an elevated risk of adverse maternal and infant birth outcomes.

METHOD

We performed a retrospective cohort study of 2,134,945 pregnancies in Quebec, Canada, from 1989 to 2016. The main exposure measure was anorexia nervosa requiring hospital treatment before or during pregnancy. Outcome measures included stillbirth, preterm birth, low birth weight, small-for-gestational age birth, preeclampsia, gestational diabetes, cesarean delivery, and other pregnancy disorders. We computed risk ratios and 95% confidence intervals (CI) for the association between anorexia nervosa and birth outcomes adjusted for maternal characteristics.

RESULTS

Compared with no hospitalization, anorexia nervosa hospitalization was associated with 1.99 times the risk of stillbirth (95% CI 1.20-3.30), 1.32 times the risk of preterm birth (95% CI 1.13-1.55), 1.69 times the risk of low birth weight (95% CI 1.44-1.99), and 1.52 times the risk of small-for-gestational age birth (95% CI 1.35-1.72). The associations with low birth weight and small-for-gestational age birth were more prominent in women hospitalized for anorexia nervosa during pregnancy or within 2 years of delivery. Hospitalization for anorexia nervosa was associated with certain maternal outcomes, including precipitate labor, acute liver failure, and admission to an intensive care unit.

DISCUSSION

Hospitalization for anorexia nervosa before or during pregnancy is associated with adverse infant and maternal outcomes. Infants are primarily at risk of stillbirth, preterm birth, low birth weight, and small-for-gestational age birth.

Maternal risk factors and adverse birth outcomes associated with HELLP syndrome: a population-based study

OBJECTIVES

We assessed the incidence, risk factors and adverse birth outcomes associated with elevated liver enzymes and low platelets (HELLP) syndrome.

DESIGN

A retrospective population-based cohort study.

SETTING

Canada (excluding Quebec), 2012/2013-2015/2016.

POPULATION

Mothers with a singleton hospital live birth or stillbirth at ≥24 weeks' gestation (n = 1 078 323).

METHODS

HELLP syndrome was identified using ICD-10-CA diagnostic code from delivery hospitalisation data. We used logistic regression to identify independent risk factors for HELLP syndrome by obtaining adjusted odds ratios (AOR) and 95% confidence intervals (CI), and to assess the associations with adverse outcomes.

MAIN OUTCOME MEASURES

Adverse maternal (e.g. eclampsia) and fetal/neonatal outcomes (e.g. intraventricular haemorrhage, perinatal death).

RESULTS

The incidence of HELLP syndrome was 2.5 per 1000 singleton deliveries (n = 2663). Risk factors included: age ≥35 years, rural residence, nulliparity, parity ≥4, pre-pregnancy and gestational hypertension and diabetes, assisted reproduction, chronic cardiac conditions, systemic lupus erythematosus, obesity, chronic hepatic conditions, placental disorders (e.g. fetomaternal transfusion) and congenital anomalies. PROM and age <25 years were inversely associated with HELLP syndrome (P-values <0.05). Women with the syndrome had a 10-fold higher maternal mortality (95% CI 1.6-84.3) and elevated severe maternal morbidity (9.6 versus 121.7 per 1000; AOR 12.5, 95% CI 11.1-14.1); and higher perinatal mortality (4.3 versus 21.0 per 1000; AOR 4.5, 95% CI 3.5-5.9) and perinatal mortality/severe neonatal morbidity (21.2 versus 202.4 per 1000; AOR 10.7, 95% CI 9.7-11.8).

CONCLUSION

HELLP syndrome is associated with specific pre-pregnancy and pregnancy risk factors, higher rates of maternal death, and substantially higher severe maternal morbidity, perinatal mortality and severe neonatal morbidity.

TWEETABLE ABSTRACT

HELLP syndrome is associated with higher maternal death rate, and substantially higher severe maternal and neonatal morbidity, and perinatal mortality.

Association of Maternal Age With Severe Maternal Morbidity and Mortality in Canada

IMPORTANCE

Over the past 2 decades, there has been a trend toward increasing maternal age in many high-income countries. Maternal age may lead to greater attendant morbidity and mortality for Canadian mothers.

OBJECTIVE

To investigate the association of maternal age, adjusting for patient-level and hospital-level factors, with severe maternal morbidity (SMM) and maternal death in Canada.

DESIGN, SETTING, AND PARTICIPANTS

A nationwide population-based cohort study of all antepartum, peripartum, and postpartum women and adolescents seen at Canadian acute care hospitals from April 1, 2004, to March 31, 2015. All analyses were completed on September 13, 2018.

EXPOSURES

Maternal age at the index delivery.

MAIN OUTCOMES AND MEASURES

Severe maternal morbidity and maternal death during pregnancy and within 6 weeks after termination of pregnancy.

RESULTS

During the study period, there were 3 162 303 new pregnancies (mean [SD] maternal age, 29.5 [5.6] years) and 3 533 259 related hospital admissions. There were 54 219 episodes of SMM (17.7 cases per 1000 deliveries) in the entire study period, with a 9.8% relative increase from 2004-2005 to 2014-2015, in addition to an increasing proportion of pregnancies to older mothers. Independent patient-level factors associated with SMM included increasing Maternal Comorbidity Index; maternal age 19 years or younger and 30 years or older, with the greatest risk experienced by women 45 years or older (odds ratio [OR], 2.69; 95% CI, 2.34-3.06 compared with maternal age 20-24 years); and lowest income quintile (OR, 1.19; 95% CI, 1.14-1.22 compared with highest income quintile). Hospital-level factors associated with SMM included specific provinces. Independent patient-level factors associated with maternal mortality included increasing Maternal Comorbidity Index, age 40 to 44 years (OR, 3.39; 95% CI, 1.68-6.82 compared with age 20-24 years), age 45 years or older (OR, 4.39; 95% CI, 1.01-19.10 compared with age 20-24 years), and lowest income quintile (OR, 4.14; 95% CI, 2.03-8.50 compared with highest income quintile). Hospital-level factors associated with maternal mortality included lowest hospital pregnancy volume.

CONCLUSIONS AND RELEVANCE

In Canada, maternal age and SMM have increased over the past decade. Results of this study suggest that province of residence, maternal comorbidity, residence income quintile, and extremes of maternal age, especially those 45 years or older, were associated with SMM and mortality. These findings are relevant to prospective parents, their health care team, and public health planning.