Polycystic ovary syndrome (PCOS) is a common endocrine disorder in reproductive-aged women, and ethnic diversity has been reported in its manifestation. This review addressed phenotype and genetic studies in Asian women with PCOS. Generally, East Asians are less hirsute, and the hirsutism score cutoff is lower than the Caucasian counterpart. It is not clear whether there are any significant differences in the prevalence or severity of irregular menstruation (IM) or characteristics of polycystic ovary (PCO) across ethnicities. Interestingly, the IM/PCO subgroup is a relatively common phenotype in East Asian patients but not in Caucasian patients. The prevalence of insulin resistance in PCOS patients varies depending on the index used and the cutoff, but women with PCOS showed a higher degree of insulin resistance than those of controls across ethnicities. Lower body mass index (BMI) and lower prevalence of metabolic syndrome were reported in East Asian patients, but despite lower BMI, a comparative study reported that Asian women with PCOS were more likely to have diabetes compared with Caucasian patients, suggesting they also have metabolic complications. Unlike East Asian patients, South Asian patients showed an increased degree of hirsutism, early onset of symptoms, and severe insulin resistance and metabolic risks compared with Caucasians. Genetic components play important roles in the pathogenesis of PCOS, and genome-wide association studies of PCOS suggest that similar genetic risk factors exist between Asian and Caucasian patients. Continuous comparative studies are needed to standardize the diagnosis and management of PCOS across different ethnicities.

Objective To investigate changes in glycaemic status in women with polycystic ovary syndrome (PCOS). Design Longitudinal observational study. Patients Women with PCOS who underwent baseline and follow‐up screening tests for diabetes (n = 262). Four patients with type 2 diabetes (T2DM) at baseline and 6 patients who were taking drugs at the final follow‐up were excluded. Measurements Changes in glycaemic classification based on fasting glucose, haemoglobin A1c and oral glucose tolerance test. Results The median length of follow‐up was 2.9 years. The mean age and body mass index in the normoglycaemia group (n = 202) were 23.0 years and 21.6 kg/m2, while it was 23.6 years and 22.9 kg/m2 in the prediabetes group (n = 50). In the normoglycaemia group, 38 (18.8%) and 2 (1.0%) developed prediabetes and T2DM, respectively. In the prediabetes group, 22 (44.0%) remained in the same category, 6 (12.0%) developed T2DM, while 22 (44.0%) achieved normoglycaemia. The incidence rate of T2DM was 9.3 per 1,000 person‐years, which was significantly higher than that of the female population of similar age, and the incidence was higher in women with fasting glucose ≥ 5.6 mmol/L at baseline than in women with < 5.6 mmol/L. Conclusions About 20% of normoglycaemic women had developed prediabetes or T2DM after a median time of 2.9 years. Meanwhile, nearly half of prediabetes women achieved normoglycaemia. Higher baseline fasting glucose levels were associated with an increased incidence of T2DM. Our results are the first to evaluate glycaemic status changes using all three parameters in patients with PCOS.

The balance between coagulation and fibrinolysis is an essential part in early pregnancy. Mutations in methylenetetrahydrofolate reductase (MTHFR) gene lead to decreased activity of the enzyme and hyperhomocysteinemia, which then induces platelet aggregation by promoting endothelial oxidative damage, possibly resulting in adverse effect on maintenance of pregnancy. We investigated the role of MTHFR single nucleotide polymorphisms (SNPs), C677T and A1298C, in Korean patients with recurrent pregnancy loss (RPL). We conducted a prospective case-control study in the Korean population. Subjects included 302 women with 2 or more consecutive, unexplained, spontaneous miscarriages before 20 weeks of gestation and 315 control women without a history of recurrent miscarriages. The genotyping for C677T and A1298C polymorphisms was performed using the TaqMan assay. Continuous variables were compared using Student's t-test, and χ2 test was used to evaluate differences in the genotype distributions between the RPL and the controls. The genotype distribution of both polymorphisms in the RPL group did not differ from those of the controls. For further analysis, if RPL patients were divided according to the numbers of pregnancy losses (≥ 2 and ≥ 3) neither group was significantly different compared with controls. MTHFR gene C677T and A1298C polymorphisms are not associated with idiopathic RPL in Korean women, suggesting that those may not be susceptible allelic variants or be deficient to cause RPL.