Maternal education and racial/ethnic disparities in nulliparous, term, singleton, vertex cesarean deliveries in the United States

AJOG Glob Rep. 2021 Dec 4;2(1):100036. doi: 10.1016/j.xagr.2021.100036. eCollection 2022 Feb.

Abstract

Background: Racial and ethnic disparities in obstetrical and neonatal outcomes are prevalent in the United States. Such racial or ethnic disparities have also been documented in the prevalence of cesarean deliveries.

Objective: We aimed to evaluate the impact of maternal education on racial or ethnic disparities in the prevalence of low-risk nulliparous, term, singleton, vertex cesarean deliveries in the United States.

Study design: This is a retrospective analysis of the Centers for Disease Control and Prevention live births database (2016-2019). Nulliparous, term, singleton, vertex births from the following racial/ethnic groups were included: non-Hispanic White, non-Hispanic Black, non-Hispanic Asian, and Hispanic. Pregnancies complicated by gestational or pregestational diabetes mellitus and hypertensive disorders were excluded. Data were analyzed on the basis of the level of maternal education (less than high school graduate, high school graduate, college graduate, and advanced degree). We compared the prevalence of cesarean deliveries among the different racial or ethnic groups within each education level using Pearson chi-square test with Bonferroni adjustment. Multivariate logistic regression was performed to assess the association between cesarean deliveries and maternal race/ethnicity, maternal education, and the interaction between maternal race or ethnicity and education level, while controlling for potential confounders. To demonstrate the effect of the interaction, separate logistic regression models with similar covariates were performed for each education level and for each race/ethnicity group. Statistical significance was determined as P<.05, and results were displayed as adjusted odds ratios with 95% confidence intervals.

Results: The overall prevalence of cesarean deliveries during the study period was 23.4% (695,214 of 2,969,207 births). All racial or ethnic minority groups had higher rates of cesarean deliveries than non-Hispanic White women (non-Hispanic Black, 27.4%; non-Hispanic Asian, 25.6%; Hispanic, 23.0%; and non-Hispanic White, 22.4%; [P<.001 for all comparisons]). Similar racial or ethnic differences in cesarean delivery rates were detected among all education levels. Higher levels of education were associated with a lower likelihood of cesarean delivery (adjusted odds ratio, 0.88; [95% confidence interval, 0.87-0.89]) in women with advanced degrees than in women who did not graduate from high school. However, although maternal education was associated with a protective effect in non-Hispanic White and non-Hispanic Asian women (adjusted odds ratio, 0.83 [95% confidence interval, 0.81-0.85] and adjusted odds ratio, 0.81 [95% confidence interval, 0.77-0.86], respectively, for women with advanced degrees), it had a smaller protective effect in non-Hispanic Black women (adjusted odds ratio, 0.93 [95% confidence interval, 0.89-0.97]) and no protective effect in Hispanic women (adjusted odds ratio, 0.98 [95% confidence interval, 0.96-1.01]).

Conclusion: We document a significant racial/ethnic disparity in the prevalence of low-risk nulliparous, term, singleton, vertex cesarean deliveries in the United States. Furthermore, our findings suggest that although a higher level of maternal education is associated with a lower likelihood of cesarean delivery, this protective effect varies among racial or ethnic groups. Further research is needed to investigate the underlying causes for this racial/ethnic disparity.

Keywords: cesarean delivery; delivery method; education level; ethnic disparity; ethnicity; nulliparous-term-singleton-vertex; race; racial disparity.