Oral contraceptives and postmolar trophoblastic disease

One hundred patients, managed for molar pregnancy at the New England Trophoblastic Disease Center, were selected at random to determine if the contraceptive method following molar evacuation influenced the incidence of postmolar trophoblastic disease. Following molar evacuation, 58 (58%) patients used oral contraceptives and 42 (42%) patients used barrier methods (foam, condom, and/or diaphragm). Postmolar trophoblastic disease developed in 11 (18.9%) patients using oral contraceptives and in 6 (14.3%) patients using barrier methods (P greater than .10). The mean human chorionic gonadotropin (hCG) regression time after molar evacuation was 7.0 weeks in patients using oral contraceptives and 7.2 weeks in patients using barrier methods. The 2 groups of patients were comparable in age, gravidity, molar histology, pretreatment hCG titers, and exposure to prophylactic chemotherapy. Oral contraceptives do not appear to increase the risk of postmolar trophoblastic tumors and therefore may be safely prescribed after molar evacuation during the entire interval of gonadotropin monitoring.