Background The relationship between maternal education and adverse pregnancy outcomes is well documented. However, limited research has investigated maternal educational disparities in adverse pregnancy outcomes in China. This study examined maternal educational inequalities associated with adverse pregnancy outcomes in rural China.

Methods We conducted a population-based cohort study using participants enrolled in the National Free Preconception Health Examination Project in Yunnan province from 2010 to 2018. The primary outcome was stillbirth, and the secondary outcome was adverse pregnancy outcomes, defined as a composite event of stillbirth, preterm birth or low birth weight. The study was restricted to singleton births at 20–42 weeks’ gestation. Univariate and multivariate log-binomial regression models were performed to estimate crude risk ratios (RRs) and confounding-adjusted RRs (ARRs) for stillbirth and adverse pregnancy outcomes according to maternal education level.

Results A total of 197 722 singleton births were included in the study. Compared with mid-educated women, low-educated women were at a significantly increased risk of stillbirth (ARR, 1.20; 95% CI, 1.05 to 1.38) and adverse pregnancy outcomes (ARR, 1.11; 95% CI, 1.07 to 1.16). However, the risk of stillbirth (ARR, 1.16; 95% CI, 1.01 to 1.35) was significantly higher for high-educated women compared with mid-educated women.

Conclusion Compared with women with medium education level, women with lower education level were more likely to experience adverse pregnancy outcomes, including stillbirth, and women with higher education level were more likely to experience stillbirth.