Many young women with breast cancer are interested in having a biologic child in the future. However, adjuvant chemotherapy can cause ovarian toxicity and fertility naturally declines due to ovarian aging that occurs during the recommended five years of treatment with adjuvant hormonal therapy. Decisions about fertility after breast cancer are further complicated by concerns about the safety of fertility preservation and subsequent pregnancy after breast cancer, despite limited available data for safety. At the present time, the most reliable fertility preservation method for breast cancer patients is embryo cryopreservation prior to treatment, although alternative options exist. In an effort to allow women to pursue fertility preservation if warranted and avoid excessive treatment delay, it is important to consider fertility concerns early in the care of young women with breast cancer.