Achieving Pregnancy After Early Hormone Receptor-Positive Breast Cancer: Recent Evidence and Clinical Considerations

An increasing number of young women with hormone receptor-positive (HR+) early breast cancer desire pregnancy after treatment. Prolonged adjuvant endocrine therapy, concerns regarding recurrence risk, and treatment-related fertility decline have historically complicated reproductive decision-making in this population. This narrative review synthesizes current evidence on pregnancy after early HR+ breast cancer, with particular emphasis on prospective data from the POSITIVE trial. We examine the safety of temporary endocrine therapy interruption, the impact of assisted reproductive technologies (ART) in achieving pregnancy, breastfeeding feasibility and impact, hormonal predictors of fertility, pregnancy outcomes and considerations for special populations, including BRCA mutation carriers. Retrospective studies have suggested no adverse survival impact associated with pregnancy after breast cancer. The POSITIVE trial provides prospective evidence that temporary interruption of endocrine therapy to attempt pregnancy does not increase short-term recurrence risk in selected patients. Approximately three-quarters of participants achieved pregnancy. Fertility preservation and ART were commonly used and were not associated with worse short-term oncologic outcomes. Biomarkers such as anti-Müllerian hormone offer supportive but imperfect prediction of fertility potential. Breastfeeding was feasible for many women and did not adversely affect breast cancer outcomes. Available data among BRCA mutation carriers are reassuring but largely observational. Current evidence supports the safety and feasibility of pregnancy after early HR+ breast cancer in carefully selected patients. However, longer follow-up, inclusion of higher-risk populations, and evaluation of newer therapies are needed. Individualized, multidisciplinary counselling remains central to informed decision-making.