We surveyed 47 pregnancies of 17 women affected with Gaucher disease (GD) type I. In two women affected with the severe form of GD type I, no change was observed in the course of the disease during pregnancy. In one patient with the moderate form of the disease there was an exacerbation of the disease during and after pregnancy, and thereafter two subsequent pregnancies of this woman ended by early spontaneous abortion. Four women were diagnosed during their pregnancy or soon after delivery suggesting in these women an exacerbation related to pregnancy. In the other ten women there was no change in the course of the disease. In general, the pregnancies of women affected with GD were normal; however, six women needed blood transfusion during pregnancy or at delivery. From these data it is suggested that there is some risk to pregnant women affected with GD type I, and accordingly, appropriate follow-up should be planned at the beginning of pregnancy in these patients.