Three cases of multiple sclerosis associated with pregnancy are reported. Two pregnancies were carried successfully to term and one was terminated in the first trimester without evidence of a change in the course of the disease.The relationship of pregnancy to exacerbations in multiple sclerosis is still vague and requires further study. Each patient should be treated individually. Her age, parity, desire for children, and the stage and severity of the disease should be considered. Women in whom the disease is in remission will probably do well in pregnancy. If gestation takes place during an acute exacerbation, however, the prognosis may be somewhat less favorable.The management of multiple sclerosis in pregnancy should be supportive and involve special consideration of the common complications such as hyperemesis, miscarriage, blood loss, and renal infection. The occurrence of these complications is said to aggravate the disease further and in some cases may precipitate acute exacerbations.While vaginal delivery is desirable, cesarean section may, in some cases, be the most conservative. The method of delivery should depend solely upon the obstetrical indications.At present there appears to be no clear-cut indication for termination of pregnancy when it is associated with multiple sclerosis.Since there is a familial tendency in this disease, a prolonged study of the female infant would be of interest.