Pregnancy complicated by hereditary spherocytosis.

Hereditary spherocytosis is a spectrum of inherited erythrocyte membrane defects that result in hemolysis and varying degrees of anemia. Among 50 pregnancies in 23 women with spherocytosis, maternal complications were infrequent except for anemia, and perinatal outcomes were generally good. In six women, blood volume expansion estimated by 51chromium-tagged erythrocytes was similar to that for normal pregnant women. Mean red cell survival measured during seven pregnancies in six women ranged at 30-90 days, consistent with the heterogeneity of this disorder.