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Updated: Aug 7, 2026

A Hyperandrogenic Mouse Model to Study Polycystic Ovary Syndrome
Published on: October 2, 2018
Hormonal studies on women with polycystic ovaries diagnosed by ultrasound
M Obhrai1, S S Lynch, G Holder
1Department of Obstetrics and Gynaecology, Birmingham Maternity Hospital, UK.
Abstract:
Eighty-six patients were diagnosed by ultrasound to have polycystic ovaries. Twelve have fairly regular but anovular cycles (P1), 56 had oligomenorrhoea (P2) and eight had primary or secondary amenorrhoea (P3). The remaining 10 patients had raised progesterone concentrations and were excluded from the hormonal studies. Gonadotrophins, steroid hormones and sex hormone binding globulin (SHBG) were measured in all patients and the results were compared with those of 29 normal women who acted as controls. A high LH:FSH ratio was the most frequently found abnormality (raised in 68.4% of patients) followed by LH (65.8%), free testosterone (FT, calculated from total testosterone (T) and SHBG) (59.2%) and 17-OHP (48.7%). Each of these four estimations was above the normal ranges in 25% of patients: proportionally most of the results outside the normal range occurred in group P3 followed by P2 and P1 respectively. To obtain a quantitative measure of the abnormalities, results were expressed as percentages of the mean control value for each hormone and these percentages were then summated. The four measurements, LH:FSH ratio, LH, FT and 17-OHP gave abnormality scores ranging from a mean of 667 in P1 to 1189 in P3 compared with 405 in controls. Twenty-one of the 76 patients were hirsute with significantly higher androgens than the nonhirsute patients. Their mean abnormality score was 1141 compared with 855 in the non-hirsute group and they all had at least one hormonal abnormality. The study demonstrates that there is a relationship between the degree of hormonal abnormality and the menstrual irregularities and hirsutism in women with PCOS suggesting that there may be a progressive nature to the syndrome.
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