Ovarian Morphology in Girls (OMG) Longitudinal Cohort Study: Pilot Evaluation of Ovarian Morphology as a Biomarker of Reproductive and Metabolic Features During the First Gynecological Year.

PURPOSE: To establish whether aspects of ovarian morphology correlate with reproductive and metabolic features during the first post-menarcheal year using data from the Ovarian Morphology in Girls (OMG!) cohort study. The feasibility of transabdominal ultrasonography to assess ovarian features was also determined.

METHODS: Healthy adolescent females enrolled in a prospective cohort study. Study visits occurred at 6-10, 11-13, 17-19, and 23-25 months post-menarche and entailed a physical exam, transabdominal ultrasound, and fasting blood draw. Participants maintained menstrual diaries throughout the study. The present analysis reflects participants who completed the study visit at 6-10 months post-menarche. Associations between ovarian morphology or average cycle length with reproductive and metabolic features were assessed by Spearman's correlations and linear regression.

RESULTS: Forty participants enrolled in the OMG!

STUDY: Thirty-one participants initiated study procedures at 6-10 months post-menarche and data were available for analysis in 29 participants. Image quality was judged as partially visible or excellent in 90% of the left and 78% of the right ovaries assessed, with all images collected having sufficient image quality to provide measurements of at least one ovarian marker. Follicle number per ovary and ovarian volume were positively associated with anti-Müllerian hormone levels and negatively associated with fasting insulin. Average cycle length only associated negatively with triglycerides.

CONCLUSIONS: Transabdominal ultrasonography in the early post-menarcheal period provides sufficient resolution to enable estimations of antral follicle count and ovarian size. Ovarian features in early gynecological life may correspond with measures of reproductive and metabolic function.