As there is only little information on pregnancy complicated by hereditary spherocytosis, we report on 8 patients with this disorder who had a total of 19 pregnancies. 10 pregnancies occurred in patients before splenectomy, and 9 occurred after splenectomy. There were 13 term births, 4 spontaneous abortions and 2 therapeutic abortions. Of the 19 pregnancies, 8 were complicated by anemia and all were in patients without splenectomy. A hemolytic crisis was encountered in 6 pregnancies, and persistent anemia occurred in 2. Transfusion was required in 4 pregnancies. It would appear that pregnancy may precipitate hemolytic anemia but maternal morbidity and fetal outcome seem more favorable after splenectomy than before splenectomy.