Maternal short stature and under-weight status are independent risk factors for preterm birth and small for gestational age in rural Bangladesh

Background/objectives: To estimate the risks of term-small for gestational age (SGA), preterm-appropriate for gestational age (AGA), and preterm SGA associated with maternal height and body mass index (BMI) and to calculate the population attributable fractions (PAF) of term SGA, preterm AGA, and preterm SGA associated with maternal short stature. Subjects/methods: A population-based cohort of 13,230 women with pre-pregnancy height and weight followed from 2012 to 2016 in Sylhet, Bangladesh. We analyzed data of 2655 singleton live born infants. The babies born <37 weeks of gestation were considered preterm and weight <10th percentile of Intergrowth sex-specific gestational age were considered SGA. Risk factors for term SGA, preterm AGA, and preterm SGA were examined using multinomial logistic regression that estimated relative risk ratios (RRR) and 95% confidence intervals (CI). Results: Maternal short stature <145 cm was significantly associated with term SGA (RRR 1.88, 95% CI 1.37, 2.58; p < 0.001), preterm AGA (RRR 1.45, 95% CI 1.02, 2.05; p < 0.05), and preterm SGA (RRR 14.40, 95% CI 1.82, 113.85; p < 0.05). Maternal underweight status (BMI < 18.5 kg/m²) was significant predictor of term SGA (RRR 1.32, 95% CI 1.10, 1.59; p < 0.01), and preterm AGA (RRR 1.39, 95% CI 1.12, 1.71; p < 0.01). PAF for maternal short stature were 23.2, 7.3, and 73.9% for term SGA, preterm AGA, and preterm SGA, respectively. Conclusions: To address the problem of undernutrition, Bangladesh needs to strengthen implementation of its multi-sectoral nutrition program comprising nutrition specific and sensitive interventions. Implementation of the program with high coverage and quality would improve maternal nutrition and perinatal outcomes including preterm births and SGA.