Serum leptin levels in normal-weight and overweight women with polycystic ovary syndrome.

The aim of this study was to evaluate serum leptin levels in women with polycystic ovary syndrome (PCOS) and in controls with normal or abnormal body mass index (BMI), since the literature data are contradictory. The study population comprised 34 women with PCOS and 30 regularly cycling women, with normal or abnormal BMI. PCOS was defined by clinical, ultrasonographic, and hormonal findings. The women were divided into four groups according to the diagnosis of PCOS and their BMI values. In all women serum levels of FSH, LH, prolactin, testosterone, androstenedione, DHEA-S, 17alpha-OH progesterone, SHBG, insulin, glucose and leptin were determined. It was found that: (a) there was a significant interaction between BMI and PCOS in increasing serum leptin levels; (b) the dominant factor for serum leptin levels in women of all Groups was BMI, followed by insulin; (c) once we corrected for BMI, it was found that there was a significant correlation between serum leptin levels and insulin values, as well as between serum leptin levels and testosterone concentrations; and (d) the QUICKI IR formula presented the most significant correlation with serum leptin levels than the other measures of insulin sensitivity. Our results showed that serum leptin levels in a subgroup of overweight women with PCOS and insulin resistance were higher than those expected for their BMI, and therefore leptin might interfere in the pathogenesis of this syndrome.