Association between cesarean section and maternal body mass index among ever-married women with recent births in Bangladesh: evidence from the 2017-18 BDHS

BACKGROUND: Cesarean section has increased substantially in Bangladesh over the past decade, raising concerns regarding its potential associations with maternal health outcomes. Evidence suggests that mode of delivery may influence postpartum weight retention and subsequent body mass index (BMI). However, population-based evidence on the association between cesarean section (C-section) and maternal body mass index in low- and middle-income countries remains limited. This study examined the association between cesarean section and maternal BMI among ever-married Bangladeshi women with recent births using nationally representative survey data. METHODS: The current study utilized a cross-sectional data from the Bangladesh Demographic and Health Survey (BDHS) 2017-2018. The analysis was restricted to ever-married women aged 15-49 years who had at least one live birth within five years preceding the survey and had complete information on delivery mode and BMI. The outcome BMI was analyzed both as a continuous and as an ordered categorical variable classified as underweight, healthy, overweight, and obese according to the standard WHO cutoffs. Multiple linear regression models were used to examine the association between cesarean section and continuous body mass index after adjusting for sociodemographic and pregnancy-related factors. Ordinal regression models were subsequently employed to assess the relationship between delivery mode and body mass index categories. The proportional odds model was initially fitted, and the proportional odds assumption was evaluated. In the presence of assumption violation, the continuation ratio model was applied to estimate category-specific effects of cesarean section across body mass index categories. All analyses accounted for the complex survey design weights. Given the cross-sectional nature of the sampling design, the analysis was limited to assessing associations and does not imply causality. RESULTS: The multiple linear regression model showed that cesarean section was significantly associated with higher maternal BMI [Formula: see text][Formula: see text][Formula: see text] after adjustment for relevant covariates. Ordinal regression analysis indicated that the proportional odds assumption was not satisfied, suggesting that the effect of delivery mode varied across body mass index categories. Findings from the continuation ratio model showed that cesarean section was not significantly associated with the comparison between the underweight and healthy categories. However, cesarean section was significantly associated with increased odds of belonging to elevated BMI categories (e.g., overweight versus healthy, and obese versus overweight). CONCLUSION: Cesarean section was associated with higher body mass index and higher odds of belonging to elevated BMI categories among ever-married Bangladeshi women with recent births. These findings indicate an association between cesarean section and higher maternal BMI, warranting further investigation in longitudinal studies. Public health strategies aimed at promoting the appropriate use of cesarean section and strengthening postpartum weight monitoring may be beneficial, although causal relationships cannot be established from the present study.