The aim of this study was to evaluate the impact of reduced peripheral insulin sensitivity, beta cell hypersecretion and reduced hepatic insulin clearance in the hyper-insulinaemia of lean and obese PCOS patients. A total of 35 women with polycystic ovary syndrome (PCOS) and 10 lean normo-ovulatory controls underwent an oral glucose tolerance test and an euglycaemic-hyper-insulinaemic clamp study. PCOS patients were classified into four groups according to their BMI and insulin secretion (normo-lean; normo-obese; hyper-lean; hyper-obese), and results were compared between groups and with the controls. All the PCOS groups showed significantly higher insulin secretion than controls; there were no differences in insulin response to glucose load between lean and obese normo- and hyper-insulinaemic patients. Secretion of c-peptide was greater in PCOS groups than controls. All the hyper-insulinaemic PCOS patients had lower values of hepatic insulin clearance, independent of BMI, when compared either with controls (P < 0.001) or with PCOS normo-insulinaemic women (P < 0.01). Normo- and hyper-insulinaemic obese patients had similar total body glucose utilization (M value), which was lower than in lean PCOS subjects and controls. Our results suggest that evaluation of insulin resistance alone does not fully characterize the PCOS population; differences in liver metabolism of insulin are present in obese insulin resistant subjects and in lean patients with normal insulin sensitivity when divided into normo- and hyper-insulinaemic subgroups. Insulin resistance and hyper-insulinaemia may represent two distinct features of the insulin disorder in PCOS: the former appear to reflect the presence of obesity, while the latter may be a primary feature of PCOS.

BACKGROUND: The clinical heterogeneity of polycystic ovary syndrome (PCOS) is mirrored by the unceasing debate on the most appropriate diagnostic criteria. METHODS AND RESULTS: To highlight differences and inconsistencies between NIH and ESHRE/ASRM criteria, we applied them to 375 patients with oligo/amenorrhoea and signs of hyperandrogenism. Among them, we identified 273 women with PCOS according to NIH, whereas up to 345 patients fulfilled ESHRE/ASRM criteria. The 72 patients, constituting the gap between the two classifications, exhibited a lower expression of clinical signs compared with the 273 patients matching both criteria. To the whole group, we then applied the ESHRE/ASRM criteria modified to include an easily reproducible ultrasound examination of the ovarian stroma (UCSC criteria). In this way, we identified 30 women who were healthy according to all criteria, 37 affected by PCOS according only to the ESHRE/ASRM Consensus, 35 affected according only to the UCSC and ESHRE/ASRM criteria and 273 who were considered to have PCOS by all criteria. These groups showed a progressively increasing expression of PCOS features. CONCLUSION: In the grey area between NIH and ESHRE/ASRM classifications, UCSC criteria could identify a subgroup of women, missed by NIH criteria, with more pronounced stigmas than those identified by ESHRE/ASRM criteria alone, and who may profit more from a targeted therapy.

The introduction of transvaginal approach in ultrasound (US) has enabled the accurate evaluation of the structure of the ovary and stroma. Stroma represents an acknowledged US marker for polycystic ovary syndrome (PCOS). The proportion revealed between the stroma and the ovary surface in the median section (S/A ratio) had been indicated as a reliable marker for hyperandrogenism. In order to verify the feasibility of this determination in routine use and to confirm the efficacy of S/A ratio in predicting hyperandrogenism in PCOS, a multicentric study was performed in association with five Italian research groups. A total of 418 subjects of fertile age presenting oligomenorrhoea or secondary amenorrhoea, enlarged ovaries measuring >10 cm³ and/or >12 follicles measuring 2–9 mm in diameter took part in the study. Clinical, US and hormonal evaluations were performed in the early follicular phase or on random days in amenorrhoeic subjects. US assessment included ovarian volume, follicle number, ovarian and stroma area in median section. The hormonal study included a baseline plasma determination of LH, FSH, estradiol (E₂), androstenedione (A), testosterone (T), dehydroepiandrosteronesulphate, 17-hydroxy-progesterone, sex hormone-binding globulin and prolactin. Correlations and receiver operator curves were used in statistical analysis of data. S/A was found to be the best significant predictor of elevated A and T levels. In order to ascertain significant cut-off values in relation to A and T levels Youden indexes were calculated and indicated 0.32 as the best cut-off for the S/A ratio. This work underlines the importance of stroma measure in improving US diagnosis of PCOS and suggest that this parameter may be used in routine clinical practice. In fact, multicentre study demonstrated the easy feasibility of such procedure without need of sophisticated machines or intensive training for operators.