4.4. Analysis.
Comparison 4 Supplementation with iron+folic acid versus no treatment/placebo, Outcome 4 Preterm birth (less than 37 weeks of gestation): SUBGROUP ANALYSIS by gestational age at the start of supplementation.
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.