Antenatal iron-folic acid supplementation reduces risk of low birthweight in Pakistan: secondary analysis of Demographic and Health Survey 2006-2007.

The aim of the current study was to examine the impact of antenatal iron-folic acid (IFA) supplementation on perceived birth size and birthweight in Pakistan over a 5-year period from 2002 to 2006. The data source was the Pakistan Demographic and Health Survey (PDHS) 2006-2007. Information from 5692 most recent live-born infants within 5 years prior to the survey was examined. The primary outcomes were maternal perception of birth size and birthweight, and the main exposure was any use of antenatal IFA supplements. Birthweight was reported for only 10% of the live births in the PDHS 2006-2007. Multivariate logistic regression analysis was adjusted for the cluster sampling design and for 13 potential confounders. The risk of having smaller than average birth size newborn was significantly reduced by 18% (adjusted odds ratio 0.82, 95% confidence interval 0.71, 0.96) for mothers who used any IFA supplements compared with those who did not. A similar (18%), but non-significant reduction in the risk of low birthweight, was found with the maternal use of IFA supplements. The risk of having smaller than average birth size babies was significantly reduced by 19% in those women who started IFA in the first trimester of pregnancy. About 11% of babies with smaller than average birth size were attributed to non-use of antenatal IFA supplements. Antenatal IFA supplementation significantly reduces the risk of a newborn of smaller than average birth size in Pakistan. Universal coverage of supplementation would improve birth size.