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Comparison of GnRH antagonists and flareup GnRH agonists in donor oocyte cycles
Alex Y Wei1, Katherine A Mijal, Mindy S Christianson
1Department of Obstetrics, University of Oklahoma, Oklahoma City, USA.
Objective:
To compare the flareup GnRH-antagonist (GnRH-ant) and GnRH-agonist (GnRH-a) protocols in oocyte donation cycles, using the donor as her own control.
Study Design:
A retrospective review at a university-based practice of 22 oocyte donors who underwent 29 cycles using recombinant follicle-stimulating hormone (FSH) and GnRH-ant and 28 cycles using flareup GnRH-a with recombinant FSH. Recipients (n=57) were synchronized with estrogen and progesterone supplementation.
Results:
The total number of recombinant FSH used and days of stimulation were similar between the groups; however, cycle days 5 estradiol (341 +/- 40 vs. 473 +/- 62 pg/mL), peak serum estradiol (1721 +/- 170 vs. 3625 +/- 295 pg/mL) and the number of retrieved MII oocytes (17 +/- 1.5 vs. 29 +/- 7) were significantly higher in the flareup GnRH-a group. Similar fertilization rates, embryos transferred, clinical pregnancy rate/embryo transfer (44%, 11/25; vs. 55%, 15/27), delivered pregnancy rate/embryo transfer (32%, 8/25; vs. 52%, 14/27) and implantation rates (31 +/- 6% vs. 28 +/- 5%) were seen in each group.
Conclusion:
Both the flareup GnRH-a and GnRH-ant are shortened, simplified and efficacious protocols in oocyte donation cycles.
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