The efficacy of metformin and clomiphene citrate in induction of ovulation in patients with polycystic ovary syndrome

摘要

Introduction: Polycystic ovary syndrome (PCOS) is one of the most common endocrinopathies observed in 5-10% of women in reproductive age [1, 2, 3]. It is a set of ovarian disturbances that is one of the most common causes of infertility associated with chronic anovulation [4]. Clomiphene citrate (CC) remains the first line treatment used to stimulate ovulation in PCOS patients. 70-85% of women respond to clomiphene citrate stimulation of ovulation. The rate of pregnancies after CC use is in the range of 30-40% [5, 6]. Laparoscopic ovarian drilling (LOD) is a second line treatment upon failure to achieve ovulation with CC [7]. It is believed that LOD sensitizes the ovaries to clomipliene citrate and gonadotropins [3]. However, both methods are associated with numerous clinical complications such as postoperative adhesions, higher mortality rate, ovarian hyperstimulation syndrome or high treatment costs. PCOS is often accompanied by other metabolic disorders, such as obesity, tissue insulin resistance and hyperinsulinaemia. PCOS enhances the incidence of type II diabetes 3-7 times [9, 10]. Between 50 and 100% obese PCOS patients and up to 20% lean PCOS patients may be insulin resistant [11]. It is believed that high circulating insulin levels lead to excessive ovarian androgens secretion and ovulation disturbances [12]. Metformin increases tissue sensitivity to insulin and reduces hyperinsulinemia, relieving the symptoms of hyperandrogenism. Metformin treatment of PCOS women prior to planned induction of ovulation using clomiphene citrate may significantly increase the rate of achieved ovulations and pregnancies [13, 14]. According to some authors, combination of rnetformin and clomiphene citrate used to induce ovulation may increase the chances of pregnancy 3-4 times compared to clomiphene citrate alone [15].The aim of the study was to assess the efficacy of metformin and clomiphene citrate in the induction of ovulation in patients with PCOS.