Background: More than 12,000 new diagnoses of breast cancer occur annually in women <40 years old and most will become survivors. It is recommended that young women with breast cancer be counseled about fertility preservation (FP) options prior to initiation of systemic therapy if they are interested in having biologic children in the future. Decisions to pursue FP are multifactorial and current data suggest only a small proportion of women pursue FP before breast cancer treatment. This study examines the decisions and outcomes of women who pursue FP before treatment and family building after therapy. Methods: An IRB approved web-based cross-sectional survey examining decisions about FP, factors influencing decisions, and post-decision regret was administered to young (age 18-45) breast cancer survivors with stage I-III breast cancer who were either English or Spanish speaking. All women received counseling by a MSK Fertility Nurse Specialist prior to initiating cancer treatment at MSKCC in 2009-2017. Clinical data was also extracted from the medical record .Results: Our sample consisted of 211 women with a mean and median age of 34 (age range was 20-45) and 82% had ER+ disease, 19% had HER-2+ disease and 12% had triple negative breast cancer. At the time of diagnosis, 46 women (22%) had children and 173 women (61%) were married or living with a partner. 151 (72%) of study participants wanted to have (more) children, 48 (23%) were unsure and 12 (6%) did not want additional children. Prior to treatment, 172 (82%) women met with a reproductive endocrinologist (RE), and 122 (58%) underwent FP: 73 froze eggs and 49 froze embryos. After treatment, 28 (13%) women met with a RE, and 13 underwent FP: 9 froze eggs and 4 froze embryos. 26 (12%) patients opted to just use a GnRH agonist during chemotherapy. For women who froze eggs, the average number obtained was 14 pre-treatment and 18 post-treatment. Of those who froze embryos, the average number obtained was 7 both pre- and post-treatment. Concern with financial burden was noted in 58% of women. Insurance did not cover any FP treatment for 56/122 (46%) of women. 32% (39/122) of women paid $10,000 or more for their FP. Women reported that the most important factor that contributed to their FP decision was the ability to feel hopeful about their future followed by concern that they would have regrets if they did not undergo FP. Additional factors that contributed to the FP decision were the desire to have biologic children, feeling overwhelmed by the cancer diagnosis, the cost of freezing eggs or embryos and concern about taking hormone medication. Reflecting back 176 women (83%) believe they made the right decision regarding FP. After completing primary breast cancer treatment, 61 women (29%) opted to try to build their family and 42 had children: 35 gave birth and 7 used a surrogate. Currently 3 women are pregnant, and 10 are pursuing pregnancy. 19 (31%) women conceived without fertility treatment and 22 (36%) women used or are currently pursuing assisted reproduction. 1 woman used a donor egg and 15 successfully used frozen eggs/embryos harvested prior to treatment. Delay of endocrine therapy to pursue pregnancy was uncommon, reported by only 6 women. However, 23 women interrupted endocrine therapy to conceive. Conclusions: The majority of women who attempted family building after treatment were able to have children. Many of these women used eggs/embryos frozen before breast cancer treatment either by getting pregnant themselves or via surrogacy. These data stress the importance of early discussion with a fertility nurse specialist regarding risks and preservation options followed by prompt referral to a reproductive endocrinologist. In addition, FP helped women to feel hopeful about their future and the majority of women believe they made the right decision.

Citation Format: Shari B Goldfarb, Bridgette Thom, Cassandra Chang, Nadia Abdo, Andrea Carpio, Rosemary Semler, Catherine Benedict, Patricia Hershberger, Joanne F Kelvin, Mary L Gemignani. Decisions and outcomes of young women with breast cancer regarding fertility preservation before cancer treatment and family building after treatment [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P4-11-03.