American Journal of Clinical Nutrition, Vol 22, 755-766, Copyright © 1969 by The American Society for Clinical Nutrition, Inc.

Folate Activity, Vitamin B₁₂ Concentration, and Megaloblastic Erythropoiesis in Anemic Pregnant Nigerians

¹ From the Sub-Department of Hematology, University of Ibadan, Nigeria

One hundred and fifty-one pregnant and 25 recently delivered Nigerian women were seen in 1 year with a hematocrit of 23% or less, not associated with hemorrhage hemoglobinopathies, or heavy hookworm infection. The etiology of the anemia was complex, but two factors, hemolysis and megaloblastic erythropoiesis, were of prime importance; the present communication does not discuss the nature of the hemolytic process, which is thought to be the result of chronic malaria.

Megaloblastic erythropoiesis showed a close correlation with low serum folate activity, and the deficiency was the result of low intake not meeting the requirements of pregnancy and erythroid hyperplasia secondary to hemolysis. Malabsorption of folic acid was demonstrated in one of the nine patients examined. About 10% of patients with definite megaloblastic erythropoiesis had a serum folate activity within the normal range, but there was no evidence of disturbed folate metabolism as a result of iron, protein, or ascorbic acid deficiency. Infections were associated with normoblastic hypoplastic anemia but sometimes precipitated acute megaloblastic arrest of erythropoiesis.

The mean serum vitamin B₁₂ concentration of patients with megaloblastic anemia was lower than in nonanemic pregnant women, but in only one patient out of 84 was the concentration below 100 pg/ml, and it was thought unlikely that this reflected true vitamin B₁₂ deficiency.

All 156 bone marrows examined contained stainable intracellular iron, and iron-deficiency anemia in pregnancy is rare in Southern Nigeria.