Thirteen patients with pituitary tumors had a total of seventeen pregnancies. Nine of these patients were treated prior to conception (four by radiation therapy, four by hypophysectomy, and one with lergotrile); four patients received no treatment. The untreated group had a total of six pregnancies, two of which were complicated by visual symptoms which regressed spontaneously after delivery. One of the hypophysectomized patients developed diabetes insipidus at 34 weeks’ gestation which resolved spontaneously after delivery. Of the four irradiated patients, one had a child with Down’s syndrome and another had a child with multiple congenital anomalies who died. The clinical course and various modes of treatment of these patients are discussed and the pertinent literature is reviewed.