Vitamin B12 Supplementation in Addition to Folic Acid and Iron Improves Hematological and Biochemical Markers in Pregnancy: A Randomized Controlled Trial

Vitamin B12 plays an important role in cell division and is of vital importance during pregnancy. Iron and B12 deficiency increase the risk of neonatal morbidity and the outcome of the overall pregnancy. The aim of our study was to analyze whether the use of vitamin B12, with standard supplements of folic acid and iron among nonanemic pregnant women, will result in improvements of hemogram parameters in terms of hematological and biochemical markers. Study participants were 200 healthy pregnant women, randomized into an intervention group and a control group, recruited from gynecological primary care practices in Split, Croatia. In addition to standard supplementation (350 mg/day ferrous iron, 5 mg folic acid), participants in the intervention group were given 5 μg of vitamin B12 each morning for 100 days. Both biochemical and hematological measurings were conducted in two intervals: 8th–10th week of gestation and then again in the 34th–36th week of gestation. Participants in the control group were given only standard-of-care iron and folic acid supplementation. Significantly lower values of haptoglobin postintervention, compared with baseline, were found only in the intervention group; for erythrocytes, significantly lower values postintervention were found only in the control group. For parameter hematocrit, we found decreased values postintervention, compared with baseline, in both intervention and control group; however, this decrease was within the reference range for the control group, whereas it was above the reference range for the intervention group. The results of this study indicated that intervention with vitamin B12 in pregnancy reduces possibilities of the onset of anemia, but within reference range.