Implications of Insulin Resistance / Hyperinsulinemia on Reproductive Function in Infertile Women with Polycystic Ovary Syndrome

Abstract

One of the most common reproductive endocrine diseases that impact many young women worldwide is polycystic ovary syndrome (PCOS). This hormonal problem affects 4 – 18% of women of reproductive age exhibiting various symptoms, such as irregular menstruation, hirsutism, infertility and metabolic disorders (LJ. Moran, et al. 2011). These symptoms in PCOS women are strongly correlated with overweight and obesity. Also, women with PCOS are likely to have metabolic disorders, such as abnormality of glucose and lipid metabolisms that are inevitably involved in diabetes mellitus and coronary artery diseases, respectively (ML. Traub, 2011). Concerning metabolic syndrome in young women, abnormalities in glucose metabolism are seen earlier than dyslipidemia as the initial manifestation; thus, glucose metabolism is suggested to be evaluated first (A. Fulghesu, et al. 2011). Insulin resistance / hyperinsulinemia is frequently associated with 40-50 % of women having PCOS, especially obese women (JE. Nestler, et al. 2002). Furthermore, obese women with PCOS are more likely indicative of insulin resistance than lean women with or without PCOS (P. Acien, et al. 1999). It is well-known that insulin resistance manifests in glucose tolerance test (GTT) prior to diabetes mellitus and coronary artery diseases (ML. Traub, 2011). Based on the recent reports, insulin resistance / hyperinsulinemia correlates with implantation disturbances and causes infertility in PCOS women (DJ, Jakubowicz, et al. 2001). Also, it is reported that the rate of early pregnancy loss is higher in women with PCOS than in normal women (DJ. Jakubowicz, et al. 2002). Thereby, insulin resistance / hyperinsulinemia is strongly linked to women with PCOS and this correlation has to be studied in details. As for obesity and overweight, which also strongly relates with PCOS, body mass index (BMI) is suggested to contribute to severity while assessing many problems, such as miscarriage, anovulation, infertility and increased prevalence of diabetes mellitus (JX. Wang et al. 2002; RJ. Norman, et al. 2002). Also, weight reduction is effective to