TMSS Medical College Journal

Background: Maternal body mass index (BMI) is an important predictor of pregnancy outcomes; however, evidence regarding the prognostic value of third-trimester BMI in Bangladesh remains limited. This study evaluated the association between maternal BMI measured during the third trimester and maternal, obstetric, neonatal and postpartum outcomes. Materials and Methods: A prospective observational cohort study was conducted among 250 singleton pregnant women attending the Department of Obstetrics and Gynaecology, Khawja Yunus Ali Medical College Hospital (KYAMCH), Bangladesh, between January 2024 and December 2025. Participants were classified using WHO Asian BMI criteria into underweight, normal weight, overweight, and obese groups. Maternal complications, mode of delivery, neonatal outcomes, and one-year postpartum maternal and infant outcomes were compared across BMI categories using appropriate statistical tests, with p<0.05 considered statistically significant. Results: Underweight women constituted 28.4% of the cohort, whereas 22.4% were overweight or obese. Underweight mothers had significantly higher rates of anemia, preterm birth, low birth weight, and NICU admission. Conversely, overweight and obese women experienced significantly increased frequencies of gestational diabetes mellitus, pre-eclampsia, Caesarean delivery, meconium-stained amniotic fluid, fetal macrosomia, postpartum weight retention, and persistent glucose intolerance. Infants born to mothers at both BMI extremes demonstrated increased neonatal morbidity and greater NICU utilization. Conclusion: Third-trimester maternal BMI is a simple, inexpensive, and clinically valuable predictor of adverse maternal and neonatal outcomes. Routine BMI assessment during late pregnancy may facilitate risk stratification, targeted nutritional intervention, individualized obstetric management, and improved maternal and neonatal outcomes in resource-limited settings such as Bangladesh.

Maternal nutritional status is a major determinant of maternal, fetal, and neonatal health. Among availableanthropometric measures, body mass index (BMI)remains a practical, inexpensive, reproducible, andwidely applicable tool for assessing nutritional statusand stratifying obstetric risk. Both low and highmaternal BMI are associated with increased maternalmorbidity, adverse pregnancy outcomes, and neonatalcomplications.':? The coexistence of undernutritionand overweight/obesity-the “double burden of malnutrition”-is particularly important in low- andmiddle-income countries (LMICs).? A large systematicreview has demonstrated that abnormal maternal BMIis associated with preterm birth, hypertensivedisorders, operative delivery, abnormal birth weight,and neonatal intensive care unit (NICU) admission.* Bangladesh is experiencing this nutritional transition.Maternal undernutrition, anemia, and micronutrientdeficiencies remain prevalent, particularly among socioeconomically disadvantaged women, whileurbanization, dietary changes, and reduced physicalactivity have contributed to increasing overweight andobesity among women of reproductive age.*.®Maternal underweight is associated with inadequatenutritional reserves, impaired fetal growth, low birthweight (LBW), preterm birth, and _ neonatalmorbidity.?,”,* Conversely, maternal overweight andobesity increase insulin resistance, systemicinflammation, and endothelial dysfunction,contributing to gestational diabetes mellitus (GDM),hypertensive disorders, pre-eclampsia, _fetalmacrosomia, operative delivery, and Caesareansection.* 14Although BMI is ideally assessed before conception orduring early pregnancy,’ this information is frequentlyunavailable in Bangladesh because many womeninitiate antenatal care late or first present to tertiaryhospitals during the third trimester.*.° In this context,third-trimester BMI may provide a pragmatic measurefor late-pregnancy risk _ stratification. Despitephysiological gestational weight gain, late-pregnancyBMI remains associated with hypertensive disorders,GDM, operative delivery, fetal growth abnormalities,and neonatal complications.'*;'7 Prospective evidence regarding the prognostic value ofthird-trimester BMI in Bangladesh remains limited,particularly regarding postpartum maternal health andinfant outcomes.'*” Therefore, this prospectiveobservational cohort study evaluated the associationbetween third-trimester maternal BMI and maternal,obstetric, neonatal, and one-year postpartum outcomesamong women attending Khawja Yunus Ali MedicalCollege Hospital, Bangladesh. We hypothesized thatboth underweight and overweight/obesity would beindependently associated with adverse pregnancyoutcomes.