SERUM LH LEVELS IN THE DIFFERENTIAL-DIAGNOSIS OF HIRSUTE ANOVULATORY WOMEN

Polycystic ovarian syndrome (PCO) occurs frequently in hirsute patient s. A dissociated explosive response of LH to LHRH administration has b een associated with the diagnosis of PCO. Twenty-four of 58 women seen because of hirsutism were found to have ovarian dysfunction based on clinical signs such as anovulation and irregular menstrual cycles. Pla sma androgen levels were elevated in the patient group. The LHRH test (200 mug, iv) was applied to the 24 patients and compared with 13 norm al ovulatory controls. Serum FSH levels before and after the LHRH test were normal in all patients. Two patterns of LH response to LHRH stim ulation were observed: an explosive response in 17 patients (DELTA LH: 39.4 +/- 21.8 IU/l, control group: 7.35 +/- 4.4 IU/l, P<0.01) and a n ormal response in 7 patients (DELTA LH: 7.53 +/- 2.41 IU/l). There was a significant correlation (r = 0.63, P<0.05) between basal LH levels and LH response to LHRH. Sensitivity and specificity calculated for ba sal LH levels higher than 6.0 IU/l, considering the LHRH test as refer ence, were 58% and 85%, respectively. The positive predictive value me asuring the possibility of LH higher than 6.0 IU/l to be from a patien t with PCO (explosive response to LHRH) was 92%. These data suggest th at, in hirsute anovulatory patients, basal LH levels may be a good pre dictor in the diagnosis of polycystic ovarian syndrome.