PULSATILE LUTEINIZING-HORMONE SECRETION IN WOMEN WITH POLYCYSTIC-OVARY-SYNDROME UNDER CLOMIPHENE CITRATE - DIFFERENCES BETWEEN RESPONDERS AND NONRESPONDERS

Although administration of Clomiphene Citrate (CC) is an effective therapy for ovulation induction in PCO patients, 15 to 20% of PCO patients do not ovulate following CC treatment. The aim of this study was to compare the endocrine dynamics (LH pulsatile pattern, FSH and steroid hormone changes) in 6 patients who ovulated (PCOS) and 6 PCO patients who did not ovulate in response to CC (PCOR). Blood was collected at 15 min intervals for 4 hr on day 9 of the first menstrual cycle (control cycle) and on day 9 of the following (treatment) cycle. In this cycle all women received 100 mg CC/day from day 5 to day 9. LH was determined in all samples whereas FSH and estradiol were measured every 60 min. No significant differences were observed regarding the age, body mass index, degree of hirsutism, ovarian volumes and basal levels of reproductive hormones between both groups of PCO women. During the control cycle, the LH pulse amplitude and transverse LH mean concentrations in PCOR patients were higher than in PCOR patients whereas the LH pulse frequency was similar in both groups. No difference was found in FSH and estradiol values between both groups. Compared to the control cycle, PCOR patients showed no change in the pulse amplitudes and no difference in LH, FSH and estradiol values following CC treatment. In contrast, during the CC therapy in PCOS patients an increase in the LH amplitude (p < 0.05), the transverse mean LH concentration (p < 0.05), FSH and estradiol was observed.Our study shows that in PCOR patients the LH pulsatility is not modified under CC therapy. Although CC did not correct the intrinsically increased LH pulsatility in PCOS patients, these patients ovulated nevertheless. An important difference was the increase in the FSH concentration in PCOS patients exclusively. This finding may suggest that the increase in FSH is more important to initiate follicular maturation than a change in LH pulsatility in PCO patients. © 1990, J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart, New York. All rights reserved.