A flexible protocol for artificial preparation of the endometrium without prior gonadotropin-releasing hormone agonist suppression in women with functioning ovaries undergoing frozen-thawed embryo transfer cycles

Objective: To present our experience with a flexible and convenient protoco l for artificial endometrial preparation without prior GnRH agonist suppres sion in patients with functioning ovaries undergoing frozen ET. Design: Case series. Setting: An IVF unit in a university hospital. Patient(s): All patients who underwent IVF with embryo cryopreservation fro m December 1997 to June 1998 and requested transfer of their frozen-thawed embryos. Intervention(s): Controlled endometrial preparation for ET entailed the use of a fixed dose of 6 mg/d of micronized E-2, started on day 1 of the cycle , followed by concomitant administration of micronized P placed in the vagi na. Main Outcome Measure(s): Hormonal and endometrial profiles throughout the c ycle, pregnancy rate per ET, implantation rate, acid pregnancy outcome. Result(s): Of 185 treatment cycles in 140 patients, 8 cycles (4.3%) were ca nceled. In another 2 cycles, no embryos were suitable for transfer. For the remaining 175 ET cycles, the calculated pregnancy rate and implantation ra te were 21.7% and 9%, respectively. The proliferative phase could be extend ed up to 20 days but was a mean (+/-SD) of 15 +/- 1.9 days. Conclusion(s): For patients with functioning ovaries, controlled endometria l preparation for the transfer of frozen-thawed embryos can be done success fully by using oral E-2, from day 1 of the cycle followed by P preparation. Prior suppression with GnRH agonist is not necessary. (Fertil Steril(R) 19 99,71:609-13. (C)1999 by American Society for Reproductive Medicine.).