Ovarian volume, not follicle count, is independently associated with androgens in patients with polycystic ovary syndrome.

Background: Polycystic ovary syndrome (PCOS) is diagnosed based on chronic anovulation, androgen excess (clinical and/or biochemical), and polycystic ovaries in ultrasound. The aim of the present study was to evaluate which parameters in the transvaginal ultrasound (TVUS) of ovaries could be better associated with concurrent hormonal imbalance in the women with PCOS.

Methods: Using a cross-sectional design, this study focused on 61 subjects (18-40 years) with PCOS. Patients were recruited at three academic hospitals during the 2017-2019 period. PCOS was defined according to the Rotterdam criteria. The association of ovarian morphology with hormonal and metabolic feature was investigated using linear regression models, adjusted for a set of possible confounding variables including age, mensuration status and body mass index (BMI).

Results: The mean volume of both ovaries was positively associated with the total testosterone level (β = 0.025, P value < 0.001), free androgen index (β = 0.041, P value < 0.001) and luteinizing hormone/follicle stimulating hormone (LH/FSH) ratio (β = 0.032, P value = 0.004), even after adjustments made for age, mensuration status and BMI (fully-adjusted model). In contrast, in the fully-adjusted model, antral follicle count (AFC), follicle number per ovary (FNPO), ovarian area, stromal area, and ratio of stromal area to ovarian area (S/A) were not associated with androgen levels and LH/FSH ratio. In addition, after full adjustments, ovarian volume, AFC, FNPO, ovarian area, stromal area and S/A were not associated with insulin resistance, which was estimated by the homeostasis model assessment of insulin resistance (HOMA-IR).

Conclusion: Increased ovarian volume is, thus, highly predictive of hyperandrogenemia and high LH/FSH ratio in PCOS patients.