HYPERSTIMULATION FOR IVF BY THE STEP-DOWN METHOD - PRELIMINARY-RESULTS OF A PROSPECTIVE RANDOMIZED STUDY WITH OR WITHOUT LHRH AGONISTS

Twenty six normo-ovulatory patients < 38 years with tubal or idiopathi c infertility and normal sperm were treated for IVF by FSH +/- hMG and randomized into four groups: with and without LHRH agonist, << step-u p >> or << step-down >> stimulation. In the step down protocol, after 4 days with 4 amps plasmatic FSH reached its top level, then decreased Despite reduction to only two amps, estradiol continued to increase i n all the 5 women without agonist, whereas 3/7 with the long protocol were considered as low responders and stopped. The fertilization/cliva ge rate was 69,2 % in step-down and 45,7 % in step-up (p < 0,04) with the short protocol, and respectively 65,6 % and 41,9 % (p < 0,03) with the long one. The pregnancy rate was equivalent in all groups.