Micronutrient Supplementation during Pregnancy among Mildly and Non-anemic Women: Effects on Iron Status and Hemoglobin

Abstract

Objectives: Universal prenatal iron-folic acid and other micronutrient supplements are recommended to prevent anemia during pregnancy, but the evidence of their effect on iron status among women with mild or no anemia is limited. This study is to describe the iron status [serum ferritin (SF), serum transferrin receptor (sTfR), and body iron (BI)] before and after micronutrient supplementation during pregnancy. Methods: Among 834 pregnant women with mild or no anemia (Hb >110 g/L) from a subset of participants in a randomized, double-blind trial in China, women were randomly assigned to daily 400 µg folic acid (FA) (control), folic acid plus 30mg iron (IFA,), or folic acid, iron, plus 13 additional multiple micronutrients (MM) provided before 20 weeks gestation to delivery. Venous blood was collected during study enrollment (<20 weeks gestation) and at 28-32 weeks gestation. Results: At 28-32 weeks gestation , compared to FA group, both the IFA and MM group showed significantly lower prevalence of iron deficiency (ID) no matter which indicator (SF, sTfR, or BI) was used for defining ID. The prevalence of ID at 28-32 weeks gestation for IFA, MM, and FA were 35.3%, 42.7%, and 59.6% respectively using low SF; were 53.6%, 59.9%, and 69.9% respectively using high sTfR; and were 34.5%, 41.2%, and 59.6% respectively using low BI. However, there was no difference on anemia prevalence between FA and IFA or MM groups.  Conclusions: Compared to FA alone, prenatal IFA and MM supplements provided to women with no or mild anemia improved later pregnancy iron status but did not affect perinatal anemia.