Egg-donors will receive urinary FSH 150-225 IU/d in antagonist protocol cetrorelix acetate 0,25 mg/d starting five days after ovarian stimulation + GnRH agonist triggering with triptorelin 0,2 mg for final follicular maturation. Foliculometry by transvaginal ultrasound and serum analysis (estradiol, progesterone, LH and FSH) will be included for cycle monitoring.