Polycystic ovary syndrome (PCOS) is a heterogeneous disorder which manifests clinically with symptoms and signs of ovarian dysfunction such as oligoovulation or anovulation, altered ovarian morphology with polycystic ovarian structure and with androgen excess (hirsutism and/or hyperandrogenenemia). In the differential diagnosis it is necessary to exclude hyperprolactinemia and non-classic adrenal hyperplasia. PCOS is the most common disease of the endocrine and reproductive system in women, which is associated with visceral obesity, insulin resistance, impaired glucose and lipid metabolism and elevated cardiovascular risk factors [
21]. The diagnosis of PCOS is made on the basis of the existence of three specific criteria: oligo-anovulation, clinical or biochemical signs of androgens excess, and ultrasound picture assessment of ovarian polycystic morphology [
22]. According to the Rotterdam criteria, two of three diagnostic criteria are necessary for the diagnosis of PCOS [
23]. Insufficient response to infertility treatment and increased pregnancy complications risk are common findings among obese PCOS women [
24]. A rise of obesity in PCOS patients may induce the appearance of reproductive and cardiovascular disease [
25]. Bariatric (metabolic) surgery remains as a final approach in PCOS cases where previous lifestyle and pharmacological management did not produce satisfactory results [
26]. Earlier, it was found that bariatric surgery use in obese PCOS women may induce a reduction in body weight, a decrease in insulin resistance, a correction of the hirsutism score and improvements in menstruation and ovulation ([
27]; Table
1). Ovulation was established in 71% in a study of 195 anovulatory obese patients after surgery intervention. Greater weight loss was associated with ovulation regain [
28]. A meta-analysis of 29 studies published up to June 2016 was done in order to establish the presence of the disorders of gonadal function related to obesity and to assess the therapeutic response after bariatric surgery on this disorders and sex hormones [
29]. It was found that obesity-related disorders of gonadal function were very prevalent, with 36% expressed as PCOS. Resolution of PCOS was detected among 96% of them. Increase of SHBG and a decrease of estradiol and testosterone together with an improvement in hirsutism and menstruation appeared as a result of bariatric surgery. The authors concluded that bariatric surgery should be used as a first choice for the management of morbidly obese patients with disorders of gonadal function [
29]. In a large retrospective study that included 930 subjects after bariatric interventions, 44 patients with PCOS were compared with 65 controls. Significant weight loss with a significant decline in total testosterone and free testosterone appeared after bariatric surgery in PCOS patients, with simultaneous reduction of hyperandrogenism and menstrual irregularity. As a result of bariatric surgery, significant weight loss with a decrease in total and free testosterone were achieved [
25]. There is still an unsolved question among experts as to which method of bariatric surgery is best to apply in severely obese PCOS patients [
26]. The same authors suggest that AMH changes after the intervention in PCOS patient may be associated with the increase in conception rate.