This study was conducted to determine the risk of menopause and infertility in female childhood cancer survivors who received abdominal-pelvic radiation and/or chemotherapy with alkylating agents in comparison with those who were treated by nonsterilizing surgery only. Females who were diagnosed in 1964-1988 before age 20 years with a histologically confirmed malignancy and who had survived for at least 5 years, had attained age 18, and were alive at time of study were identified through the Ontario Cancer Registry. Reproductive outcomes were ascertained by a telephone-administered questionnaire, and treatment data were abstracted from medical records for 830 subjects aged 18-49 years; 719 survivors who were nonmenopausal at the end of treatment were included in the analyses. Survivors who received both alkylating agents and abdominal-pelvic radiation were more likely to be postmenopausal than were those who underwent surgery (risk ratio = 2.58; 95% confidence interval: 1.14, 5.80). Women treated with abdominal-pelvic radiation alone had a fertility deficit of 23% compared with those in the surgery group; the deficit was restricted to women diagnosed postpuberty. Risks of menopause and infertility increased with increasing dose of abdominal-pelvic radiation and amount of alkylating agent.