Prevalence of polycystic ovary syndrome in European countries and USA: A systematic review and meta-analysis

We conducted a systematic review and meta-analyses of the prevalence of Polycystic Ovary Syndrome (PCOS) and the frequency of its phenotypes in Europe and the USA, also focusing on temporal trends of the condition, to compare the PCOS prevalence among populations with a similar level of diagnostic resources availability and attitudes toward health problems, to improve comparability of estimates. We considered Europe and USA, two high-income areas with these characteristics.The overall PCOS prevalence according to the NIH1990, ESHRE/ASRM 2003, AES-PCOS diagnostic criteria was respectively 6.2 % (95%CI 5.3-7.0), 19.5 % (95%CI 17.3-21.6), and 15.0 % (95%CI 12.9-17.1), with no appreciable heterogeneity across geographic areas. Phenotype A, the complete PCOS, showed higher preva-lence in all areas (44.8%, 95%CI 40.3-49.3), followed by phenotype D, called non-hyperandrogenic PCOS (19.5%), phenotype C termed as ovulatory PCOS (16.2%), and phenotype B, presenting as phenotype A but without polycystic ovarian morphology (14.9%). In all the studies analysing temporal trends of PCOS, an in-crease in prevalence of PCOS was reported, due, at least in part, to changing diagnostic criteria.The prevalence of PCOS is similar in European countries and the USA. Interestingly, some differences in the frequency of PCOS phenotypes emerged between the two areas with a higher frequency of phenotype A and a lower one of phenotype C in the USA. Recognizing the factors which explain these differences would lead to a better understanding of the etiopathogenesis and the clinical expression of PCOS.

Automated summary

This study conducted a systematic review and meta-analyses of the prevalence and phenotypes of PCOS in Europe and the USA. The results showed similar prevalence rates of PCOS between European countries and the USA, but differences in the frequencies of PCOS phenotypes. Understanding the factors behind these differences would contribute to a better understanding of the etiopathogenesis and clinical expression of PCOS.