Abstract Introduction: Sexual dysfunction is a prevalent issue among breast cancer survivors and may have a particular impact on younger women, for whom long-term quality of life is crucial.Objectives: To explore the prevalence and predictors of sexual dysfunction in breast cancer survivors under 50 years old in Uruguay, and to assess the influence of different treatment modalities on their Female Sexual Function Index (FSFI) scores. Methods: This subgroup analysis included patients younger than 50 years from a multicenter observational ambispective study. Eligible women had completed treatment for stage I to III breast cancer (surgery, chemotherapy, and radiotherapy) at least 12 months prior. Sexual dysfunction was defined as FSFI less than or equal to 26.55. Logistic regression models were used to identify associations between treatment modalities and dysfunction. Results: Of the total cohort, 41 patients were under 50. In this group, 65.9 percent had FSFI scores indicating dysfunction. Mastectomy was associated with lower FSFI scores across all domains compared to breast-conserving surgery. The use of gonadotropin-releasing hormone agonists was significantly associated with higher odds of dysfunction (odds ratio 5.7, 95 percent confidence interval: 1.5 to 25.6). Chemotherapy showed no significant detrimental effect in this subgroup. Conclusions: Sexual dysfunction is highly prevalent among young breast cancer survivors in Uruguay and appears to be influenced by specific treatments. These findings support integrating sexual health counseling and fertility-preserving strategies into early survivorship care for this population. Citation Format: N. Camejo, C. Castillo, R. Servetto, G. Muñoz, J. Manzanares, D. Amarillo, M. Guerrina, G. Herrera, C. Dörner, G. Krygier. Sexual Function in Young Breast Cancer Survivors: A Subgroup Analysis of an Observational Study in Uruguay abstract. In: Proceedings of the San Antonio Breast Cancer Symposium 2025; 2025 Dec 9-12; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2026;32(4 Suppl):Abstract nr PS1-04-19.
Camejo et al. (2026) studied this question.