Effect of iron supplementation and its frequency during pregnancy

The iron (Fe) nutritional status of 203 healthy pregnant women was assessed at the first prenatal visit (To) (gestational age: 16.9 weeks +/- 3.8). Wo men were randomly assigned to one of three groups: G1 and G2 were supplemen ted with ferrous fumarate (60 mg elemental Fe) daily or intermittently (thr ee times a week), respectively; and GC was the control group, without suppl ementation. The follow up was carried out until 34-37 weeks of gestational age (Tf), but only 43% of pregnant women completed the trial. At To and Tf fasting blood samples were collected and Hematocrit (Hct), Hemoglobin (Hb), Erythrocyte Protoporphyrin (EP) and Serum Ferritin (FERR) were determined. The percentage of women with abnormal biochemical values at To (n = 203) w as: Hb (g/dl) < 10.5: 2.6%; PE (mu g/dl of red blood cells) > 70: 4.8%; FER R (ng/ml) < 10: 4.4%. Results ((X) over bar +/- DE) of women that completed the follow up were at To and Ti, respectively: Hct (%): GC: 37.7 +/- 3.4 a nd 36.0 +/- 3.2 (p < 0.05); G1: 38.8 +/- 2.2 and 38.0 +/- 2.6; G2: 39.0 +/- 2.7 and 37.7 +/- 3.7; Hb (g/di): GC: 12.5 +/- 1.2 and 11.9 +/- 1.3 (p < 0. 05); G1: 12.6 +/- 1.1 and 12.8 +/- 1.1; G2: 12.9 +/- 0.9 and 12.2 +/- 1.5; PE (mu g/dl red blood cells): GC: 30 +/-. 17 and 43 +/- 22 (p < 0.01); G1: 26 +/- 13 and 38 +/- 21 (p < 0.01); G2: 26 +/- 16 and 31 +/- 26; FERR (ng/m l): GC: 75 +/- 67 and 31 +/- 49 (p < 0.01); G1: 46 +/- 34 and 19 +/- 10 (p < 0.01); G2: 43 iii and 11 +/- 7 (p < 0.01). These results show: a) Fe admi nistration was efficient to mitigate Hb decrease; b) Fe stores decreased du ring pregnancy regardless of Fe supplementation and frequency; c) EP values indicate that intermittent Fe administration was more efficient to maintai n normal erythropoiesis.