Polycystic ovary morphology is associated with insulin resistance in women with polycystic ovary syndrome

Abstract

Background/objectives: Polycystic ovary syndrome (PCOS) is a heterogeneous disorder characterized by chronic anovulation, hyperandrogenism, polycystic ovary morphology (PCOM) and metabolic disturbances including insulin resistance and type 2 diabetes mellitus. Although insulin resistance could be associated with PCOM, recent studies have shown controversial results. The aim of this study was to determine the relationship between PCOM and insulin resistance.

Subjects/methods: This was a cross-sectional clinical study. A total of 679 women with PCOS who were diagnosed using the National Institute of Child Health and Human Disease (NICHD) criteria and 272 control women were analysed. We measured fasting glucose and insulin levels, 75 g oral glucose tolerance test-derived glucose and insulin levels, testosterone levels, ovarian volume and follicle number.

Results: Polycystic ovary morphology was described in 543 women (80.0%) with PCOS. Women with PCOS had significantly higher 2 hours postload glucose, fasting and 2 hours postload insulin levels, ovarian volume, ovarian follicle numbers and lower insulin sensitivity compared with those of the controls (all P<.01). In women with PCOS, ovarian volume and ovarian follicle number were negatively associated with the quantitative insulin sensitivity check index after adjusting for age, body mass index and total testosterone; however, this association was not observed in the controls. In the logistic regression analysis, increased ovarian follicle number was associated with decreased insulin sensitivity in women with PCOS.

Conclusions: In PCOS, enlarged ovarian volume and follicle excess were associated with insulin resistance, and the number of ovarian follicles could be a predictor of insulin resistance.

Keywords: insulin resistance; polycystic ovary morphology; polycystic ovary syndrome.