Gonadotropin-releasing hormone (GnRH) analog suppression renders polycystic ovarian disease patients more susceptible to ovulation induction with pulsatile GnRH.

Pulsatile GnRH administration consistently restores normal reproductive hormone levels and ovulation in women with hypogonadotropic hypogonadism, but is less effective in those with polycystic ovarian disease (PCOD). We pharmacologically created a hypogonadotropic condition with a GnRH analog (GnRH-A) in six women with PCOD to investigate the role of deranged gonadotropin secretion in PCOD and to improve the response to pulsatile GnRH ovulation induction. Before GnRH and GnRH-A treatment the women with PCOD had increased LH pulse frequency [one pulse every 55 +/- 2 (+/- SE) min; P less than 0.05] and LH pulse amplitude (10.9 +/- 1.4 U/L; P less than 0.05) compared to normal women in the follicular phase of their menstrual cycle. Each PCOD woman completed one cycle of pulsatile GnRH administration for ovulation induction before (pre-A cycles; n = 6) and one or two cycles after (post-A cycles; n = 9) GnRH-A administration [D-Ser(tBu)6-Des,Gly10-GnRH; 300 micrograms, sc, twice daily for 8 weeks]. Pulsatile GnRH (5 micrograms/bolus) was given at 60-min intervals using a Zyklomat pump. Daily blood samples were drawn during the pulsatile GnRH ovulation induction cycles for the determination of serum LH, FSH, estradiol (E2), progesterone, and testosterone, and pelvic ultrasonography was done at 1- to 4-day intervals. Mean (+/- SE) serum LH levels were elevated during the pre-A cycle (49.2 +/- 3.1 IU/L) and decreased to normal levels during the post-A cycles (19.6 +/- 1.4 IU/L; P less than 0.0001). Mean testosterone concentrations were lower during the post-A cycles [88 +/- 2 ng/dL (3.1 +/- 0.1 nmol/L)] than during the pre-A cycles [122 +/- 3 ng/dL (4.2 +/- 0.1 nmol/L); P less than 0.0001]. In the follicular phase of the post-A cycles E2 levels were significantly lower [81 +/- 5 pg/mL (300 +/- 20 pmol/L) vs. 133 +/- 14 pg/mL (490 +/- 50 pmol/L); P less than 0.0001], preovulatory ovarian volume was smaller (24.6 +/- 2.0 vs. 31.4 +/- 2.4 cm3; P less than 0.01), and the FSH to LH ratio was higher (0.56 +/- 0.03 vs. 0.16 +/- 0.01) than in the pre-A cycle, suggesting more appropriate function of the pituitary-gonadal axis. Excessive LH and E2 responses to pulsatile GnRH administration in the early follicular phase of the pre-A cycle were abolished in the post-A cycles.(ABSTRACT TRUNCATED AT 400 WORDS)