SAT-132 Ovarian Function and Follicular Reserve in Patients Who Underwent Oncological Treatment Before and After Puberty

Abstract Disclosure: K.N. Maidana: None. M.E. Escobar: None. E.J. Moratto: None. L.N. Coscia: None. M.C. Riccheri: None. M.S. Bonifacio: None. S.A. Varela: None. M.F. Perez: None. L.M. Sacconi: None. V.A. Viale: None. M.V. Forclaz: None. Introduction: The life expectancy of girls and adolescents with cancer has improved due to early diagnosis and effective treatments. However, secondary adverse effects may cause endocrine-reproductive disorders. Objective: To assess ovarian function and follicular reserve in patients undergoing cancer treatment before and after puberty. Population andMethods: Observational, descriptive, cross-sectional study. Patients with history of oncological disease in the childhood-juvenile stage treated at the Professor Alejandro Posadas National Hospital were studied between 11/01/2020 and 10/31/2022 by determining AMH, antral follicle count and FSH levels. The participants were recruited during the follow-up of cancer treatment. Descriptive statistics were presented, with comparisons using the Mann-Whitney test for continuous variables and Chi-square/Fisher tests for categorical variables. Results: 71 participants were evaluated. 40 had the cancer diagnosis when they were prepubertal (56%) and 31 after having started puberty (44%). The median age at the start of cancer treatment was 8.1 years (0.9-17.6), at the end was 10.1 years (2.1-20.3). The median years of follow-up were 11.8 years (5-25) and at the evaluation was 19.9 years (10.8-31.9). 53% received only chemotherapy treatment (CMT), 15.5% (CMT+RT); 15.5% (QMT+ Surgery). All participants who received BMT (8.4%) had impaired ovarian function and follicular reserve. 68 had menarche at 12.2 years ± 1.2; 55 had regular cycles, 27 were under treatment with contraceptives or hormone replacement therapy. The AMH value was 2.4 ng/ml (0.02-7.8) in those who had a prepubertal diagnosis and 1.9 ng/ml (0.1- 6.5) in those who had a diagnosis after puberty, p=0.05. The AMH value was <1 ng/ml in 17% in those who had the diagnosis before puberty and 32%, in those who had the diagnosis after puberty; p=0.14. 9 of the 57 had FSH values ​​≥25 mIU/ml (16%). The median FSH value was 7.48 mIU/ml (2.5-166) in 33 patients diagnosed before puberty and 8.5 mIU/ml (4.9-201) in 24 patients diagnosed after puberty (p=0.03). The FSH value was ≥25 mIU/ml in 6.1% (2/33) of prepubertal diagnoses and 29.2% (7/24) of post-pubertal diagnoses (p=0.027). Transvaginal ultrasound was performed in 37 patients, with RFA <5 in 11. RFA was <5 in 37% of prepubertal diagnoses and 32% of post-pubertal diagnoses. Conclusion: Ovarian reserve was affected in 17% of those diagnosed before puberty and 32% of those diagnosed after puberty. Although a trend was observed between the values ​​of both groups, the difference was not significant, p=0.05. Ovarian function according to FSH values ​​was significantly different in 6.1% and 29.2% of those diagnosed before and after puberty. The impairment of fertility was closely related to the therapy received. Presentation: Saturday, July 12, 2025