Pregnancy After Breast Cancer: A Narrative Review of Oncologic Safety, Obstetric and Neonatal Outcomes, and Reproductive Survivorship.

Background: Survival after early breast cancer has improved to the point where reproductive health is no longer a peripheral concern in young survivors but a routine one. This review synthesizes current evidence on oncologic safety, obstetric and neonatal outcomes, fertility preservation, breastfeeding, and psychosocial survivorship to develop a counseling framework that clinicians can apply in practice. Methods: This narrative review was informed by a structured literature search of PubMed/MEDLINE, Embase, and the Cochrane Library covering studies published from January 2000 to July 2026, with greater analytic weight given to studies published from 2010 onward to ensure the synthesis reflects contemporary treatment standards. Relevant evidence was identified and narratively synthesized according to the clinical and reproductive aspects of pregnancy after breast cancer. No formal risk-of-bias assessment or quantitative synthesis was undertaken. Results: On the currently available evidence, pregnancy after breast cancer is not associated with an increased risk of recurrence. This holds in hormone receptor-positive disease and in BRCA1/2 carriers, and it is supported prospectively by the POSITIVE trial, whose preplanned update at a median follow-up of 71 months found a five-year incidence of breast cancer-free interval events of 12.3% against 13.2% in matched external controls. Obstetric and neonatal risks are higher than in the general obstetric population, although the pooled effect sizes are small to moderate: odds ratios are approximately 1.14 for cesarean delivery, 1.45 for preterm birth, 1.50 for low birth weight, and 1.16 for small-for-gestational-age birth. The excess concentrates in pregnancies conceived within the first one to two years after diagnosis and attenuates thereafter. Fertility preservation techniques appear both effective and oncologically safe. Fertility-related distress, by contrast, is common and does not reliably resolve once treatment ends. Conclusions: Oncologic risk alone is not a reason to advise against pregnancy after breast cancer. Early oncofertility referral, multidisciplinary planning, and risk-adapted obstetric surveillance remain the priorities. Because the evidence base is predominantly observational, these conclusions describe what the current data show rather than establishing safety definitively.