Child marriage in rural Bangladesh and impact on obstetric complications and perinatal death: Findings from a health and demographic surveillance system.

Adolescent pregnancies, a risk factor for obstetric complications and perinatal mortality, are driven by child marriage in many regions of South Asia. We used data collected between 2017-2019 from 56,155 married adolescents and women in a health and demographic surveillance system to present a population-level description of historical trends in child marriage from 1990-2019 as well as epidemiologic associations between maternal age and pregnancy outcomes in Baliakandi, a rural sub-district of Bangladesh. For pregnancies identified between 2017-2019, we used Kaplan-Meier estimates to examine timing of first pregnancies after first marriage and multinomial logistic regression to estimate associations between maternal age and perinatal death. We described the frequency of self-reported obstetric complications at labor and delivery by maternal age. In 1990, 71% of all marriages were to female residents under 18 years of age. This decreased to 57% in 2010, with the largest reduction among females aged 10-12 years (22% to 3%), and to 53% in 2019. Half of all newly married females were pregnant within a year of marriage, including adolescent brides. Although we observed a decline in child marriages since 1990, over half of all marriages in 2019 were to child brides in Baliakandi. In this same population, adolescent pregnancies were more likely to result in obstetric complications (13-15 years: 36%, 16-17 years: 32%, 18-34 years: 23%; χ2 test, p<0.001) and perinatal deaths (13-15 years: stillbirth OR 2.23, 95% CI 1.01-2.42; 16-17 years: early neonatal death OR 1.57, 95% CI: 1.01-2.42) compared to adult pregnancies. Preventing child marriage can improve the health of girls and contribute to Bangladesh's commitment to reducing child mortality.