Characteristics of different phenotypes of polycystic ovary syndrome based on the Rotterdam criteria in the Croatian population

The aim of this study was to calculate the relative prevalence of all phenotypes of polycystic ovary syndrome (PCOS) and to compare them for anthropometrical, hormonal and metabolic differences according to the Rotterdam Criteria. A total of 300 women with PCOS aged 26.7 +/- 5.6 years (mean +/- SD) and 100 women aged 28.3 +/- 4.1 years (mean +/- SD) were included in a control group. Anthropometrical, hormonal and metabolic parameters were compared between the groups. The most prevalent phenotype in our population was the most severe, phenotype A (56.7%), followed by phenotype D (26.7%) and phenotype C (14.3%). Phenotype B was present in only 2.3% of patients. The four main phenotypes did not differ in age, BMI and WHR. Women with phenotypes A and C had increased levels of LH and an increased LH/FSH ratio along with elevated androgen levels compared to the other groups. Serum glucose levels did not differ between the groups studied, however, higher levels of insulin, GIR and HOMA-IR were found between phenotype A and the control group. Phenotype C PCOS or ovulatory PCOS have the same characteristics as classic PCOS, however in a more mild form, which represents a transition between the classic form and the control group. Compared to the control group, phenotype D had higher mean levels of serum testosterone (still within normal range) along with elevated LH levels and LH/FSH ratio, similar to classic PCOS. However, compared with women diagnosed with PCOS based on hyperandrogenism, oligo-ovulation and polycystic ovaries, these patients demonstrated milder endocrine and metabolic abnormalities. Therefore, from an endocrine point of view, our study supports the inclusion of a normoandrogenic anovulatory phenotype in PCOS diagnostic criteria.