Purpose: This study was undertaken to determine the effect, if any, of treatment for cancer diagnosed during childhood or adolescence on fertility.
Patients and methods: We reviewed the fertility of female participants in the Childhood Cancer Survivor Study (CCSS), which consisted of 5-year survivors, and a cohort of randomly selected siblings who responded to a questionnaire. Medical records of all members of the cohort were abstracted to obtain chemotherapeutic agents administered; the cumulative dose of drug administered for several drugs of interest; and the doses, volumes, and dates of administration of all radiation therapy.
Results: There were 5,149 female CCSS participants, and there were 1,441 female siblings of CCSS participants who were age 15 to 44 years. The relative risk (RR) for survivors of ever being pregnant was 0.81 (95% CI, 0.73 to 0.90; P < .001) compared with female siblings. In multivariate models among survivors only, those who received a hypothalamic/pituitary radiation dose > or = 30 Gy (RR, 0.61; 95% CI, 0.44 to 0.83) or an ovarian/uterine radiation dose greater than 5 Gy were less likely to have ever been pregnant (RR, 0.56 for 5 to 10 Gy; 95% CI, 0.37 to 0.85; RR, 0.18 for > 10 Gy; 95% CI, 0.13 to 0.26). Those with a summed alkylating agent dose (AAD) score of three or four or who were treated with lomustine or cyclophosphamide were less likely to have ever been pregnant.
Conclusion: This large study demonstrated that fertility is decreased among female CCSS participants. The risk factors identified may be utilized for pretreatment counseling of patients and their parents.