Body mass index in early-pregnancy and selected maternal health outcomes: Findings from two cohorts in Bangladesh

Background Maternal nutrition is one of the most influential factors that affect the health of the mother and her offspring and remains a significant public health challenge globally. There is a lack of studies evaluating the trends of maternal nutrition and its impact on the burden of pregnancy complications from low-income countries, including Bangladesh. We aimed to determine the burden of early-pregnancy nutrition status based on body mass index (BMI), and the associations of nutritional status with pregnancy-induced hypertension (PIH), cesarean section (CS) delivery, perineal tear and postpartum hemorrhage (PPH) in a rural area in Bangladesh. Methods This prospective study analyzed data from two cohorts: the Maternal, Neonatal, and Child Health (MNCH) project carried out from January 2008 to June 2010, and the Preterm and Stillbirth Study, Matlab (PreSSMat) conducted from October 2015 to March 2018. In total, information of 9287 women who gave birth from the two cohorts was available for analysis. Early-pregnancy BMI was categorized into underweight, normal-weight, and overweight groups. The change in the burden of malnutrition between two cohort periods and the associations between women's BMI and maternal health outcomes were presented in odds ratios (ORs) with their 95% confidence interval (CI). Results Between the two cohort periods, the prevalence of underweight decreased from 17.5% to 15.4%, and overweight increased from 10.8% to 20.9%. The risk of being overweight in pregnant women was about two times (OR = 2.19; 95% CI = 1.94-2.46) higher in the PreSSMat cohort than in the MNCH cohort. After multivariate-adjustment for socio-demographic factors, the pooled ORs of PIH, CS delivery, perineal tear, and PPH were 2.41 (95% CI = 1.95-2.99), 2.12 (95% CI = 1.86-2.41), 2.46 (95% CI = 1.54-3.92), and 1.68 (95% CI = 1.12-2.53), respectively, in women with overweight compared to the normal-weight group. Conclusions The results confirmed the existence of a double burden of malnutrition in rural women in Bangladesh. Women with overweight had an increased risk of selected pregnancy complications. The findings call for the adoption of appropriate prenatal counseling and preparedness tailored to women's nutritional status to prevent possible adverse health outcomes.