Pregnancy in beta-thalassemia trait carriers: an uneventful journey.

Normochromic normocytic anemia during pregnancy reflects the significant increase in plasma volume, which disproportionately exceeds the increase in the red cell volume. In beta-thalassemia (beta-thal) trait carriers who become pregnant the plasma volume expansion may cause more pronounced anemia because the anemia of pregnancy is added to the pre-existed hypochromic microcytic anemia. In beta-thal women, pregnancy outcome and obstetric complications do not differ from the general population. Anemia in beta-thal carriers is generally not severe enough to warrant anxiety. No specific therapy is indicated and pregnant women generally require only supportive care with an anticipated favorable pregnancy outcome.