LONG-TERM DOWN-REGULATION DOES NOT IMPROVE PREGNANCY RATES IN AN IN-VITRO FERTILIZATION PROGRAM

Objective: To investigate the effects of long-term down-regulation (4 months) used in combination with gonadotropin ovarian stimulation for IVF-ET. Design: Prospective randomized study. Setting: Assisted Reprod uction Unit of the Hospital Clinic i Provincial in Barcelona, a tertia ry care setting. Patient(s): Thirty pairs of IVF patients who were mat ched for age, indication for IVF, and number of attempts. Intervention (s): Women were randomized to receive a standard long protocol of SC l euprolide acetate (n = 30, group L) or a monthly injection of leuproli de acetate depot for 4 months (n = 30, group D) before gonadotropin st imulation. Main Outcome Measure(s): Ovarian response and IVF outcome. Result(s): Days of ovarian stimulation, follicular recruitment and gro wth during gonadotropin treatment, and the endometrial thickness on th e day of hCG administration were similar for the 2 groups of NF patien ts. However, the serum concentration of E-2 was significantly higher i n group L even though group D received a higher total dose of gonadotr opins. The number of follicles punctured, the number of oocytes retrie ved, the number of oocytes fertilized, the number of embryos suitable for replacement and cryopreservation, the number of patients with ET, and implantation and clinical pregnancy rates were similar for groups L and D. However, the percentage of metaphase II oocytes was significa ntly higher in group L than in group D. Conclusion(s): Long-term down- regulation does not improve pregnancy rates in a general IVF program. (Fertil Steril(R) 1998;70:46-51. (C)1998 by American Society for Repro ductive Medicine.).