Distinct Reproductive Phenotypes Segregate With Differences in Body Weight in Adolescent Polycystic Ovary Syndrome.

INTRODUCTION: Polycystic ovary syndrome (PCOS) is a heterogenous clinical syndrome defined by hyperandrogenism and irregular menses. In adult women with PCOS, discrete metabolic and reproductive subgroups have been identified. We hypothesize that distinct phenotypes can be distinguished between adolescent girls who are lean (LN-G) and girls with obesity (OB-G) at the time of PCOS diagnosis.

METHODS: Data were extracted from the CALICO multisite PCOS database. Clinical data collected at the time of diagnosis were available in 354 patients (81% with obesity) from 7 academic centers. Patients with body mass index (BMI) < 85th percentile for age and sex were characterized as lean (LN-G) and those with BMI percentile ≥ 95th percentile as obese (OB-G). We compared metabolic and reproductive phenotypes in LN-G and OB-G.

RESULTS: Reproductive phenotypes differed between the groups, with LN-G having higher total testosterone, androstenedione, and LH levels, while OB-G had lower sex hormone binding globulin (SHBG) and higher free testosterone. Metabolic profiles differed as expected, with OB-G having higher hemoglobin A1c, alanine aminotransferase, and serum triglycerides and more severe acanthosis nigricans.

CONCLUSION: LN-G with PCOS had a distinct reproductive phenotype characterized by increased LH, total testosterone, and androstenedione levels, suggesting neuroendocrine-mediated ovarian androgen production. In contrast, phenotypes in OB-G suggest hyperandrogenemia is primarily driven by insulin resistance with low SHBG levels. These observations support the existence of distinct metabolic and reproductive subtypes in adolescent PCOS characterized by unique mechanisms for hyperandrogenemia.