Racial variations of adverse perinatal outcomes: A population-based retrospective cohort study in Ontario, Canada

Abstract

Introduction Racial differences in adverse maternal and birth outcomes have been studied in other countries, however, there are few studies specific to the Canadian population. In this study, we sought to examine the inequities in adverse perinatal outcomes between Black and White pregnant people in Ontario, Canada. Methods We conducted a population-based retrospective cohort study that included all Black and White pregnant people who attended prenatal screening and had a singleton birth in any Ontario hospital (April 1st, 2012-March 31st, 2019). Poisson regression with robust error variance models were used to estimate the adjusted relative risks of adverse perinatal outcomes for Black people compared with White people while adjusting for covariates. Results Among 412,120 eligible pregnant people, 10.1% were Black people and 89.9% were White people. Black people were at an increased risk of gestational diabetes mellitus, preeclampsia, placental abruption, preterm birth (<37, <34, <32 weeks), spontaneous preterm birth, all caesarean sections, emergency caesarean section, low birth weight (<2500g, <1500g), small-for-gestational-age (<10th percentile, <3rd percentile) neonates, 5-minute Apgar score <4 and <7, neonatal intensive care unit admission, and hyperbilirubinemia requiring treatment but had lower risks of elective caesarean section, assisted vaginal delivery, episiotomy, 3rd and 4th degree perineal tears, macrosomia, large-for-gestational-age neonates, and arterial cord pH≤7.1, as compared with White people. No difference in risks of gestational hypertension and placenta previa were observed between Black and White people. Conclusion There are differences in several adverse perinatal outcomes between Black and White people within the Ontario health care system. Findings might have potential clinical and health policy implications, although more studies are needed to further understand the mechanisms.

Racism and Pregnancy Health in Hamilton, Ontario

“…Such inequities in geographic and socio-economic exposures offer a plausible mechanism for racialized respondents' being at increased risks of reporting pregnancy complications and lower-than-recommended pregnancy weight gain . These proposed explanations also apply to interpreting similar observations reported in three recent epidemiological studies on pregnancy and birth outcomes in Ontario 16,18,46 and to a comparative US-Canada epidemiological study on racialized inequities in premature births. 17 While these four studies show that non-white Canadians differ from white Canadians in regard to pregnancy health risks, they do not offer structural or sociological explanations for these differences.…”

“…14 Here, we address some of these blind spots in the framing and measurement of racism in Canadian public health during the critical lifecourse stage of pregnancy. 9,15 Complementary to recent epidemiological studies already showing differences in pregnancy outcomes in regard to "racial" categories in Canada, [16][17][18] we investigated links between racialization and pregnancy health in ways attendant to participants' experiences and attitudes. Our project, called the Mothers to Babies (M2B) study, used a mixed-methods, community-level exploratory approach [19][20][21] that gathered and analyzed qualitative data from 10 focus-group discussions and one stakeholder meeting, which integrated diverse perspectives from care receivers, care providers, and other relevant stakeholders.…”

Association of birthweight with diabetes, hypertension, and ischemic heart disease in young adulthood: a retrospective cohort study

“…28 The literature shows considerable variation in cardiometabolic risk and adverse perinatal outcomes including low birthweight by race or ethnicity. [37][38][39][40][41][42][43] Race and ethnicity are important variables to identify and measure health inequalities that stem from racism, bias, and discrimination, providing insight for potential clinical and health policies. 44 Another limitation was the lack of data on the indication for caesarean section, which could further elucidate potential pathways leading to cardiometabolic outcomes.…”

The RESPCCT Study: Community-led Development of a Person-Centered Instrument to Measure Health Equity in Perinatal Services

“…Using maternal mortality rates as an indicator of quality perinatal care, rates in Canada suggest relatively high-quality care when compared to low-and middle-resource countries (United Nations Maternal Mortality Estimation Inter-agency Group, 2023). However, there are considerable perinatal health disparities between Indigenous (Bacciaglia et al, 2023;Kolahdooz et al, 2016;Miao Id et al, 2022;Turpel-Lafond, 2020), Black, and the predominately white populations living in Canada (McKinnon et al, 2016;Miao Id et al, 2022). Recent immigrants or refugees, people who identify as Indigenous (First Nation, Inuit, and Métis), people from racial, sexual, and gender minority groups, and those who live with disabilities are also more likely to have increased perinatal morbidities, including miscarriage, stillbirth, low birth weight infants, preterm birth, postpartum depression, post-traumatic stress disorder, reductions in breastfeeding rates, and a host of other poor perinatal outcomes (Bacciaglia et al, 2023;H.…”

“…Recent immigrants or refugees, people who identify as Indigenous (First Nation, Inuit, and Métis), people from racial, sexual, and gender minority groups, and those who live with disabilities are also more likely to have increased perinatal morbidities, including miscarriage, stillbirth, low birth weight infants, preterm birth, postpartum depression, post-traumatic stress disorder, reductions in breastfeeding rates, and a host of other poor perinatal outcomes (Bacciaglia et al, 2023;H. K. Brown et al, 2021;Center for Disease Control & Prevention, 2023;Chartier et al, 2022;Everett et al, 2019;Miao Id et al, 2022;Tarasoff et al, 2020). These disparities are compounded among those with multiple marginalized identities (Center for Disease Control & Prevention, 2023;Everett et al, 2019;National Academies of Sciences, Engineering, Medicine, 2021).…”