The aim of the study is to analyze treatment-induced gonadal damage and premature ovarian failure after adoptive cell therapy (ACT) after a cytotoxic lymphodepleting preparative regimen. Records of 66 consecutive females who received ACT at the Surgery Branch, National Cancer Institute, NIH (Bethesda, MD) were reviewed. Patients received a conditioning regimen of high-dose cyclophosphamide (60 mg/kg x 2 doses) and fludarabine (25 mg/m² x 5 doses). Some patients also received total body radiation at 200 or 600 cGy. Assessment of ovarian function was determined by analysis of monthly follicle stimulating hormone (FSH) levels, menstrual history, and symptoms. Among patients with serum available and normal pretreatment ovarian function, 21 had a preparative regimen with chemotherapy alone and 5 patients had received chemotherapy with total body radiation. Nine (43%) patients in the chemotherapy cohort and all 5 patients in the chemotherapy plus total body radiation cohort had persistently elevated FSH levels and were given the diagnosis of premature ovarian failure. Twelve (57%) patients had normal FSH levels at 6 months posttreatment. Median age of all patients at treatment was 34 years. Median age of women retaining normal ovarian function was 30 (range, 19-45) vs. 41 years (range, 30-49) for those who did not regain function. The conditioning regimen of 2 doses of cyclophosphamide (60 mg/kg) and 5 doses of fludarabine (25 mg/m²) may induce gonadal damage and premature ovarian failure. Younger age at treatment was associated with a higher frequency of normal ovarian function posttreatment, whereas adding total body radiation was associated with a high risk of ovarian failure.