Chemotherapy may induce acute ovarian failure, but in women who retain gonadal function throughout chemotherapy, the late effects upon ovarian function are unknown. A retrospective controlled survey was performed to ascertain whether chemotherapy for gestational trophoblastic tumours (GTT) results in premature menopause. Questionnaires were sent to 1,489 women diagnosed between 1971 and 1990 with GTT, including 1089 who had received chemotherapy and 400 who had not received chemotherapy (controls). Responses were obtained from 972 chemotherapy-treated patients and 327 controls. 124 women were not evaluable for menopause date as they had undergone hysterectomy as part of the treatment for GTT or had developed permanent amenorrhoea during chemotherapy. Overall, 172 women reported that they were postmenopausal, including 157 women who had received chemotherapy. The median age at menopause for the evaluable population was 50 years (range 25-56 years). The age at menopause was significantly earlier in the treated arm (median 50, range 25-56 years) than in the controls (median 53, range 40-57 years) (logrank test chi 2 = 12.6, P = 0.0004). Menopause occurred significantly earlier in women treated with combination chemotherapy (median 49, range 25-56 years) compared with single agent methotrexate (median 51, range 25-56 years) (logrank test chi 2 = 8.3, P = 0.004). However, the age at completion of chemotherapy in the treated arm did not influence the age of menopause (proportional Hazards chi 2 = 1.99, P = 0.16). Chemotherapy for GTT induces menopause 3 years earlier than it occurs in women with GTT who do not receive chemotherapy. Although the difference is statistically significant, the magnitude is modest and most women can be reassured that neither fertility nor postmenopausal osteoporosis will be greatly affected.