Objective: Guided by the favorable results of pulsatile gonadotrophin-releasing hormone (GnRH) in the recovery phase after GnRH agonist (GnRH-a) in PCOS, two hypotheses concerning the recovery phase were tested: (1) The resistance to clomiphene citrate will be broken in the recovery phase. (2) Stimulation with (i) a fixed dose of follicle stimulating hormone (FSH) or (ii) with the GnRH-a itself is equally effective in inducing ovulation as pulsatile GnRH.
Design: After discontinuation of a 17-21 days GnRH-a treatment, ovulation induction was attempted with clomiphene citrate (CC) or with a fixed dose of FSH or with GnRH-a itself in three separate pilot trials. A previously reported group of 12 patients, treated with pulsatile GnRH in the recovery phase served as control.
Patients: Three groups of six patients having PCOS. The group treated with CC was a selected CC-resistant group.
Results: No CC-treated patient ovulated. After FSH stimulation two patients ovulated, and one patient ovulated on stimulation with a low dose of the GnRH-a. Endocrine observations in the recovery phase showed an early rise of FSH as compared to the rise of LH and androgens.
Conclusion: This study could not demonstrate any effect of the recovery phase with respect to facilitation of follicular growth in PCOS. Both tested hypotheses were rejected: (1) The resistance to CC appeared not to be broken by the GnRH-a treatment and (2) subsequent stimulation with FSH or with the GnRH-a itself were not as effective as stimulation with pulsatile GnRH. An extensive further study of the mentioned modalities did not seem feasible.