Follicular development and hormone concentrations following recombinant FSH administration for anovulation associated with polycystic ovarian syndrome: prospective, randomized comparison between low-dose step-up and modified step-down regimens.

The present study compared ovarian performance and hormone concentrations, after ovulation induction, in polycystic ovarian syndrome (PCOS) patients, using recombinant human FSH (rhFSH) in low-dose step-up and modified step-down regimens. Twenty-six women with clomiphene citrate-resistant chronic anovulatory infertility were treated with rhFSH in two consecutive cycles according to two different low-dose regimens: (i) the classic chronic low-dose step-up protocol, the starting dose being 75 IU; (ii) a modified step-down protocol where the starting dose was 300 IU followed by 3 days free of treatment, then rhFSH 75 IU daily was given and stepwise dose increments were performed exactly the same as in the step-up method. Each woman received both treatment approaches, in a randomized order, with an interval of > or = 1 month between treatments. The total number of follicles that were > 10, > 14 and > 17 mm in diameter on the day of human chorionic gonadotrophin (HCG) administration, and thus cycles with HCG cancelled, were significantly increased with the step-up approach. The total number of rhFSH ampoules tended to be higher with the step-down schedule despite the fact that both the mean duration of treatment and the threshold dose were similar with the two low-dose approaches. A physiological step-down approach for ovulation induction in PCOS patients may be more appropriate in order to avoid multifollicular cycles than the step-up approach.