We previously demonstrated that birth weight was higher among infants born to women receiving SQ-LNSs (which contained 20 mg Fe) than among infants of women receiving iron and folic acid capsules (which contained 60 mg Fe), even though the iron and folic acid group had higher mean Hb concentration, higher iron status, and a lower prevalence of anemia at 36 weeks of gestation (18, 22). This evidence concerns the gene GSTM1 and anemia (phenotype).