Rates of childbirth in female cancer survivors: A population-based study in Taiwan.

Abstract

As cancer survival improves, increasing numbers of women diagnosed during their reproductive years face potential fertility impairment. However, population-based evidence on post-cancer childbearing remains limited in Asian settings. We conducted a nationwide cohort study in Taiwan by linking the Cancer Registry, Birth Reporting Registry, and Death Registry. A total of 72,929 females diagnosed with cancer at age ≤ 39 years were followed to identify subsequent livebirths. The cumulative incidence of first post-diagnosis livebirth was estimated using competing-risk methods. Predictors were evaluated using cause-specific Cox models. Standardized birth ratios (SBRs) were calculated by comparing observed births with expected births in the general population, standardized by age and calendar year. Overall, 9.8% of female cancer survivors had at least one livebirth after diagnosis. The 5-, 10-, and 15-year cumulative incidences were 6.4%, 10.7%, and 13.9%, respectively. Compared with the general population, survivors had approximately half the expected number of births (SBR = 0.50; 95% CI, 0.49-0.51). Substantial heterogeneity was observed across cancer types: childbirth was most preserved among survivors of thyroid and skin cancers, whereas those with cervical, uterine, breast, leukemia, and central nervous system cancers had markedly reduced childbirth. Older age at diagnosis and receipt of chemotherapy were strongly associated with lower likelihood of childbirth. In this large, nationwide study, female cancer survivors in Taiwan experienced substantially reduced childbirth rates, with pronounced variation by cancer type, age at diagnosis, and treatment. These findings provide robust population-level evidence from an Asian context and highlight the need for early fertility counseling and improved access to oncofertility care.