Late Effects of the Reproductive System
Fertility was evaluated among the 5,149 female CCSS participants and 1,441 female siblings of CCSS participants, aged 15 to 44 years. The RR for ever being pregnant was 0.81 (95% CI, 0.73–0.90; P < .001) compared with female siblings. In multivariate models among survivors only, those who received a hypothalamic/pituitary radiation dose of greater than 3,000 cGy (RR = 0.61; 95% CI, 0.44–0.83) or an ovarian/uterine radiation dose greater than 500 cGy were less likely to have ever been pregnant (RR = 0.56 for 500–1000 cGy; 95% CI, 0.37–0.85; RR = 0.18 for >1000 cGy; 95% CI, 0.13–0.26). A summed alkylating agent dose score of 3 (RR = 0.72; 95% CI, 0.58–0.90; P = .003) or 4 (RR = 0.65; 95% CI, 0.45–0.96; P = .03) was associated with lower observed risk of pregnancy compared with those with no alkylating agent exposure. Those with a summed alkylating agent dose score of 3 or 4 or who were treated with lomustine or cyclophosphamide were less likely to have ever been pregnant. A follow-up study of the same cohort demonstrated impaired fertility in female survivors who received modest doses (22–27 Gy) of hypothalamic pituitary radiation and no or very low doses (<0.1 Gy) of ovarian radiation, providing support for the contribution of the role of luteal phase deficiency to infertility in some women.
Fertility may be impaired by factors other than the absence of sperm and ova. Conception requires delivery of sperm to the uterine cervix, patency of the fallopian tubes for fertilization to occur, and appropriate conditions in the uterus for implantation. Retrograde ejaculation occurs with a significant frequency in men who undergo bilateral retroperitoneal lymph node dissection. Uterine structure may be affected by abdominal irradiation. A study demonstrated that uterine length was significantly shorter in ten women with ovarian failure who had been treated with whole abdomen irradiation. Endometrial thickness did not increase in response to hormone replacement therapy in three women who underwent weekly ultrasound examination. No flow was detectable with Doppler ultrasound through either uterine artery of five women, and through one uterine artery in three additional women.