title: Results with GnRH antagonist protocols are equivalent to GnRH agonist protocols in comparable patient populations.
abstract: OBJECTIVE
  To determine whether ovarian stimulation outcome and success rates are equivalent between GnRH agonist and GnRH antagonist regimens when all other variables are held constant.
  
  
  METHODS
  Retrospective analysis. Infertile patients (n = 1,277) < 35 years of age, with normal ovarian reserve, undergoing their first in vitro fertilization cycle with a GnRH antagonist or agonist were included. Outcome variables were analyzed and compared between both groups.
  
  
  RESULTS
  Of the total number of patients included, 21% (n = 268) underwent stimulation with a GnRH antagonist protocol and 79% (n = 1,009) with an agonist protocol. While the mean number of embryos transferred was similar between both groups, as well as the implantation rate for blastocyst embryo transfers, the implantation rate was noted to be slightly higher for the down-regulation group who underwent a Day 3 embryo transfer (p = 0.01). However, the overall clinical pregnancy, loss and high-order multiple pregnancy rates were constant in both groups.
  
  
  CONCLUSIONS
  Although numerous variables were analyzed in our study, the differences noted did not have an impact on our final results as the clinical pregnancy rates were maintained in the antagonist group.
authors.affiliation: Division of Reproductive Endocrinology, Department of Obstetrics and Gynecology, Mount Sinai Medical Center, New York, New York 10022, USA.
authors.forename: Martha
authors.initials: M
authors.lastname: Luna
authors.forename: Gerardo
authors.initials: G
authors.lastname: Vela
authors.forename: Casey A
authors.initials: CA
authors.lastname: McDonald
authors.forename: Alan B
authors.initials: AB
authors.lastname: Copperman
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D004334:Drug Administration Schedule; D004624:Embryo Transfer / Q000706:statistics & numerical data; D005260:Female; D005300:Fertility Agents, Female / Q000008:administration & dosage*; D007987:Gonadotropin-Releasing Hormone / Q000008:administration & dosage* / Q000819:agonists / Q000031:analogs & derivatives; D006801:Humans; D007273:Injections, Intramuscular; D009519:New York City; D010062:Ovulation Induction / Q000379:methods*; D011247:Pregnancy; D011256:Pregnancy Outcome; D012189:Retrospective Studies
chemical_list: D005300:Fertility Agents, Female; D007987:Gonadotropin-Releasing Hormone