Maternal erythropoietin in singleton pregnancies: a randomized trial on the effect of oral hematinic supplementation

Our purpose was to study the effect of hematinic supplementation on the maternal erythropoietin response during singleton pregnancy.

In a randomized, double-blind trial 97 patients with a first-trimester hemoglobin level > or = 14.0 gm/dl received either iron and folic acid (hematinic group, n = 53) or a placebo (n = 44). Serial hemoglobin, hematocrit, and serum erythropoietin were recorded from maternal blood and from cord blood on delivery. Serum ferritin was measured in the first trimester, at 36 weeks' gestation, and in cord blood.

In both groups (1) the mean hemoglobin was lower (p < 0.01) at 40 weeks' gestation than when first examined and (2) the mean serum erythropoietin was higher (p < 0.01). The mean serum ferritin was lower (p < 0.001) in both groups at 36 weeks' gestation than at presentation but higher (p = 0.04) in the hematinic group than in the placebo group. The mean hemoglobin and hematocrit were similar in the two groups until the third trimester but thereafter were higher (p < 0.05) in the hematinic group. The mean maternal serum erythropoietin was higher (p < 0.05) in the placebo group than in the hematinic group after 24 weeks' gestation. The mean cord blood hematologic values were similar in the two groups.

Maternal serum erythropoietin increased during pregnancy, but this response was reduced in the third trimester in the hematinic-supplemented group.