Breast cancer and fertility.

OPINION STATEMENT: The increased availability of assisted reproductive technologies (ART) allows women with fertility issues to increase their chances of a successful pregnancy with the use of medications that, in some cases, increase circulating estrogens. There has been significant concern that the use of these medications will increase the risk of hormone-sensitive cancers such as breast, ovarian and uterine malignancies. Additionally, for those women who are diagnosed with a breast cancer during their reproductive years, this diagnosis can be particularly difficult as future fertility is a major concern for many young breast cancer survivors. With the current available data, there does not appear to be a statistically significant increase in the risk of developing breast cancer with ART, although several series suggest a potential possible related increase in borderline ovarian and uterine cancers. For breast cancer survivors, there does not appear to be an increased risk of death associated with subsequent pregnancies when compared with breast cancer patients who did not have subsequent pregnancies, although waiting at least 2 years after the diagnosis of breast cancer potentially may convey a protective effect. Therefore, when systemic therapy for breast cancer is recommended, early counseling and referral to a reproductive endocrinologist is warranted to provide optimal fertility preservation options. Further safety and outcomes studies are warranted for children.