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 modifiedstep-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-d own regimens. Twenty-six women with clomiphene citrate-resistant chronic an ovulatory infertility were treated with rhFSH in two consecutive cycles acc ording 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 tre atment, 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 bo th treatment approaches, in a randomized order, with an interval of greater than or equal to1 month between treatments. The total number of follicles that were >10, >14 and >17 mm in diameter on the day of human chorionic gon adotrophin (HCG) administration, and thus cycles with HCG cancelled, were s ignificantly 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 simila r with the two low-dose approaches. A physiological step-down approach for ovulation induction in PCOS patients may be more appropriate in order to av oid multifollicular cycles than the step-up approach.