Relationship of Antenatal Iron-folic Acid (IFA) Supplementation and Birth Size: Evidence from Nepal
Yasir B. Nisar *
The University of Sydney, Sydney, NSW, Australia.
Michael Dibley
The University of Sydney, Sydney, NSW, Australia.
*Author to whom correspondence should be addressed.
Abstract
Objectives: To determine the effect of antenatal IFA supplementation on maternal perceived birth size in Nepal using pooled data from 3 Nepal Demographic and Health Survey (DHS) 2001, 2006 and 2011.
Methods: We used survival information from 13,111 most recent live-born infants. Primary outcome was maternal perceived birth size and the main exposure variable was the antenatal IFA supplementation. Birth weight was reported in 19% of live births. Perceived birth size was considered as surrogate for birth weight. Data was analysed by using STATA 13 and adjusted for the cluster sampling design. Analyses used multivariate logistic regression adjusted for 18 potential confounders.
Results: Maternal use of IFA supplementation during pregnancy significantly reduced the risk of less than average birth size by 15% (aOR: 0.85 p=0.01) compared to no IFA use after adjustment for other confounders. The protective effect of IFA supplementation on less than average birth size remained there whether other antenatal services used or not (aOR: 0.81, p=0.001) compared to no IFA supplementation and no antenatal services. A slightly greater magnitude of protective effect was observed when mother used ≥90 supplements in their pregnancy (aOR: 0.84, p=0.03) than those mothers who never used any IFA supplements after adjustment for other confounding factors.
Conclusions: Maternal use of IFA supplements during pregnancy significantly reduces the risk of less than average birth size in Nepal. The magnitude of protective effect on the risk of having less than average birth size was greater in infants whose mothers used ≥90 supplements in their pregnancy.