Maternal and perinatal outcome in relation to hemoglobin concentration and serum ferritin examined between 16 and 20 weeks of gestation

Background: Anemia is a major health problem among women of reproductive age, particularly in developing countries. Our aim was to investigate the relation between hemoglobin concentration and serum ferritin and pregnancy outcome. Methods: In a prospective longitudinal study, 382 pregnant women attending University Hospital Zurich, Switzerland for antenatal care and delivery in the period 2004 to 2005 were included. Venous blood samples were examined for hematological status and serum ferritin between 16 and 20 weeks and for hemoglobin concentration before delivery. The adverse maternal and perinatal outcomes were determined. Multiple logistic regression analysis was performed to establish if anemia and low serum ferritin early in the second trimester are independent risk factors for well-known pregnancy complications. Results: Iron deficiency anemia was observed in 6.5%, depleted iron stores in 32.2% and anemia for other reason in 11.8%. A higher parity was observed in patients with iron deficiency anemia (p=0.029) and in patients with depleted iron stores (p=0.005). Depleted iron stores were higher in patients from former Yugoslavia (p=0.038) and anemia for other reason in patients from developing countries (p=0.008). There was no increase of prenatal, peripartal or postpartal complications in patients with mild anemia and in patients with depleted iron stores. The mean hemoglobin concentration before delivery was 121±12g/l. The multiple logistic regression analysis showed that anemia and depleted iron stores are not independent risk factors for adverse outcomes. Conclusions: Mild anemia and depleted iron stores detected early in pregnancy were not associated with adverse maternal and perinatal outcomes.