Objective: This study was undertaken to determine the effect, if any, of prior treatment with radiation therapy or chemotherapy for cancer diagnosed during childhood or adolescence on pregnancy loss, live births, and birth weight.
Study design: We reviewed pregnancy outcome among female participants in the Childhood Cancer Survivor Study (CCSS) who returned a questionnaire. Eligibility for the CCSS included 5-year survivors who were <21 years old at diagnosis and who were diagnosed with an eligible cancer between January 1, 1970, and December 31, 1986, at the 25 participating CCSS institutions. The questionnaire included items regarding attempts to become pregnant, the occurrence of pregnancy, and the outcome of pregnancy (ie, live birth, stillbirth, miscarriage, abortion). 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, anatomic regions, and dates of administration of all radiation therapy.
Results: One thousand nine hundred fifteen females reported 4029 pregnancies (63% live births, 1% stillbirths, 15% miscarriages, 17% abortions, 3% unknown or in gestation). There were no significant differences in pregnancy outcome by treatment. A higher, but not statistically significant, risk of miscarriage was present among women whose ovaries were in the radiation therapy field (relative risk [RR] 1.86, P =.14), were near the radiation therapy field (RR 1.64, P =.06), or were shielded (RR 0.90, P =.88). The rate of live birth was not lower for the patients treated with any particular chemotherapeutic agent. The offspring of the patients who received pelvic irradiation were more likely to weigh <2500 g at birth (RR 1.84, P =.03).
Conclusions: This large study did not identify adverse pregnancy outcomes for female survivors treated with most chemotherapeutic agents. The offspring of women who received pelvic irradiation are at risk for low birth weight.