Synergistic associations of antenatal care visits and iron-folic acid supplementation with low birth weight: A pooled analysis of national surveys from six South Asian countries

Background: The prevalence of low birth weight (LBW) has remained high in the South Asian region with a significant impact on newborn survival. While antenatal care (ANC) and iron-folic acid supplementation independently have been considered effective interventions to improve maternal and newborn outcomes, the evidence on the combined effect of these two services with LBW is lacking. This study aimed to examine the synergistic impact of ANC and iron-folic acid supplementation on LBW in the South Asian region using pooled data from six countries. Methods Nationally representative surveys from Nepal, India, Bangladesh, Pakistan, Maldives, and Afghanistan were included in the study. Birth weight and the prevalence of LBW for singleton last-born children were reported using descriptive statistics. The association between LBW and ANC visits and the two-way interaction between iron-folic acid consumption and ANC were examined using multiple logistic regression. Results Mean birth weight in the region was 2841.8 grams with a LBW prevalence of 17.1%. Country-specific prevalence ranged from 11.4% in Nepal to 22.4% in Pakistan. Not attending ANC visits (adjusted odds ratio (AOR): 1.24; 95% confidence interval (CI): 1.16, 1.34) and not consuming iron-folic acid (AOR: 1.14; 95% CI: 1.08, 1.21) were significantly and positively associated with a higher likelihood of LBW. Furthermore, jointly, having < 4 ANC visits and < 180 days of iron-folic acid supplementation was associated with a higher likelihood (AOR: 1.29; 95% CI: 1.22, 1.36) of having LBW infants compared to those who had had ≥ 4 ANC visits and ≥ 180 days of iron-folic acid after controlling for key confounding factors. Conclusions The current study provides important evidence on the synergy between ANC visits and iron-folic acid supplementation during pregnancy to capitalize on the existing national maternal health programs in the South Asian region, including low-and middle-income countries for positive foetal outcomes.