Purpose: To determine FSH concentration behavior before and after cetrorelix 0.25 mg administration in the GnRH-antagonist multiple-dose protocol on day 6 of ovarian stimulation with 150-300 IU daily recombinant FSH.
Methods: Blood samples for FSH measurements were drawn from seven women every 15 min from 8 h prior to the first cetrorelix administration in the GnRH-antagonist multiple-dose protocol until 15-32 h thereafter.
Results: No significant change of FSH concentration was observed.
Conclusions: This observation indicates that no rationale exists of increasing the daily FSH dosage concomitantly to the GnRH-antagonist administration to compensate for a drop of endogenous FSH.