PSUN373 Early Evidence for Ovarian Morphology as a Biomarker of Reproductive and Metabolic Health During the First Gynecological Year

INTRODUCTION: Ovarian transabdominal ultrasonography (TAUS) is not recommended in the assessment of adolescent reproductive health. We have previously demonstrated feasibility of ovarian TAUS in adolescents with polycystic ovary syndrome (PCOS) as well as the utility of ovarian features to reflect the degree of reproductive symptomology in these older teens. Whether this feasibility and ovarian biomarker capability extends to the early post-menarcheal years is unknown. OBJECTIVES: To determine the feasibility of TAUS to image ovarian morphology in early gynecological life, and to determine whether ovarian features reflect degree of metabolic or reproductive status as compared to menstrual cycle length. METHODS: 31 healthy adolescents are enrolled in a prospective cohort study monitoring ovarian morphology, reproductive health, and metabolic status during the first 2 years post-menarche. At 6-10 months post-menarche, all participants underwent a physical exam, TAUS and a fasting blood draw to measure reproductive hormones, lipids, and insulin. Self-recorded menstrual cycles were categorized as "irregular" if any of the three previous inter-menstrual-intervals (IMIs) were <21 or >45 days and "regular" if all three previous IMIs were 21-45 days. IMI groups were compared via Mann-Whitney U-tests. Spearman's rho correlations evaluated associations between ovarian variables, mean IMI, and reproductive and metabolic endpoints. RESULTS: Resolution of ovarian morphology was possible in all but one participant (97%). Overall image quality was judged as partially visible or excellent in 70% of the left ovaries and 80% of the right ovaries assessed. 19 participants were classified as having irregular cycles (61%), 10 as having regular cycles (32%), and 2 participants as undetermined (7%) within the first year of menarche. Reproductive, metabolic, and ovarian endpoints did not differ by cycle status (Mann-Whitney U-tests, P>0.05). Both the number of 2-9mm antral follicles per ovary (FNPO) and ovarian volume (OV) were positively associated with anti-Müllerian hormone (ρ=0.66, P<0.01; 0.55, P<0.01) and negatively associated with fasting insulin (ρ=-0.42, P<0.05; -0.51, P<0.01). FNPO was also positively associated with total testosterone (ρ=0.34, P<0.1) and negatively associated with waist-to-hip ratio (ρ=-0.32, P<0.1). Ovarian features were not associated with clinical measures of hyperandrogenism (hirsutism score). Unlike aspects of ovarian morphology, IMI was only significantly associated with triglycerides (ρ=-0.39, P<0.05). CONCLUSION: Transabdominal ovarian imaging during the early post-menarcheal period is feasible and provides sufficient resolution to enable the identification of antral follicles and ovarian size. Unlike IMI, ovarian features in early gynecological life correspond with measures of both reproductive and metabolic health. Similar to adults, we provide evidence that ovarian morphology may represent a clinically feasible biomarker to monitor reproductive health in early gynecological life. Whether ovarian features change as reproductive dysfunction, such as PCOS manifests will be determined in follow-up studies within this longitudinal cohort. Presentation: Sunday, June 12, 2022 12:30 p.m. - 2:30 p.m.