Vitamin B12 Pregnancy Supplementation

Pregnancy is associated with increased requirements for iron and increased blood volume of up to 40%. Because expansion in plasma volume is higher than the increase in the mass of red blood cells, there is a fall in hemoglobin concentration, which leads to physiological anemia, characterized with lower hemoglobin (Hb), hematocrit and red blood cells, but without changes in mean corpuscular volume (MCV). Anemia in pregnancy is defined with Hb values under 110 g/L in the first trimester and under 105 g/L in the second and third trimester.

Iron deficiency is thought to be the most common nutrient deficiency among pregnant women. Consequences of anemia include delayed fetal growth, premature delivery, intrauterine fetal death, postpartum depression and delayed psychomotor development of a child. It is known that in women that are not anemic daily iron supplementation of 27 mg/day is sufficient, which can be obtained from adequate nutrition or body supplies. Iron supplementation is pregnancy has been recommended by the WHO (World Health Organisation) since 1959, and this recommendation was confirmed by numerous professional associations. However, in women with anemia, or women subjected to particular dietary regimens with diminished quantity of iron, including vegetarian or vegan diet, required supplementation dosage is higher, and estimated in the literature to be 120 mg/day.

The aim of this study was to analyze whether adding vitamin B12 (5 µg /100 days), along with folic acid and iron as supplement in pregnant women who are not anemic and who need only iron supplementation, will result in improvements of hematological and biochemical markers.