Fertility preservation and infertility treatment in breast cancer patients.

About 12% of breast cancer cases occur before the age of 35 years. Thus, young patients may consider preservation of ovarian function during cytotoxic therapy and/or childbearing after treatment. Besides the exposure to cytotoxic agents over several months, a significant number of patients will need sequential antihormonal therapy for years. Thus, even young patients at diagnosis may have to postpone pregnancy for years. At that time, the probability of pregnancy may per se be considerably reduced. Young patients per se carry a worse prognosis compared to their postmenopausal counterparts. Ovaries may harbor viable tumor cells. Premenopausal patients have a higher prevalence of BRCA gene mutation than older patients. Thus, even if the ovaries are preserved, the risk of developing cancer in the ovary may be high. Normal menstrual cyclicity after chemotherapy/antihormonal therapy does not preclude premature ovarian failure. After antineoplastic therapy, it is recommended to wait at least for two months before the evaluation of the ovarian function. The most reliable parameter to assess the ovarian reserve is the anti-muellerian factor (AMH; Muellerian Inhibiting Factor, MIF). Four randomized studies have investigated the protective effect of the GnRH analogue goserelin on ovarian function. Due to the inconsistent results observed, the concurrent administration of GnRH analogues with cytostatic chemotherapy now has to be considered experimental and cannot be recommended. Emergency in vitro fertilization may be performed between breast cancer diagnosis and the start of chemotherapy in selected cases. Extracorporal in vitro fertilization may be performed and the resultant embryo cryopreserved to preserve fertility.