title: A GnRH agonist and exogenous hormone stimulation protocol has a higher live-birth rate than a natural endogenous hormone protocol for frozen-thawed blastocyst-stage embryo transfer cycles: an analysis of 1391 cycles.
abstract: OBJECTIVE
  To compare embryo and birth data in cryopreserved-thawed blastocyst-stage ET cycles between natural endogenous hormone cycles and exogenous hormone stimulation cycles.
  
  
  METHODS
  Retrospective cohort analysis.
  
  
  METHODS
  Large academic assisted reproductive technology center.
  
  
  METHODS
  One thousand three hundred ninety-one patient cycles undergoing frozen-thawed blastocyst-stage ET cycles.
  
  
  METHODS
  Live-birth rate.
  
  
  METHODS
  The synthetic protocol used GnRH agonist followed by estrogen and P. The natural protocol used monitoring and post-transfer P.
  
  
  RESULTS
  The patients in the two protocols had similar baseline characteristics. Multiple linear regression showed the synthetic protocol to have a higher live-birth rate (odds ratio [OR], 1.46; 95% confidence interval [CI], 1.02-2.09). In patients having two embryos transferred, the synthetic stimulation protocol resulted in a higher live-birth rate per cycle start (32.3% vs. 20.4%; relative risk [RR], 1.58; 95% CI, 1.22-2.06). Similarly, patients with one or two embryos transferred who had additional cryopreserved blastocysts available also had a higher live-birth rate per cycle start (36.1% vs. 12.1; RR, 2.98; 95% CI, 1.16-7.63).
  
  
  CONCLUSIONS
  The synthetic hormone protocol was associated with a higher live-birth rate when compared with a natural cycle protocol for frozen-thawed blastocyst-stage ET cycles. This improvement persisted when analysis was controlled for cycle cancellation. The synthetic stimulation protocol for frozen-thawed embryo cycles offers improved outcome results for patients.
authors.affiliation: Reproductive Biology and Medicine Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Building 10, CRC, Room E1-3140, 10 Center Drive, Bethesda, Maryland 20892, USA. hillmicah@mail.nih.gov
authors.forename: Micah J
authors.initials: MJ
authors.lastname: Hill
authors.forename: Kathleen A
authors.initials: KA
authors.lastname: Miller
authors.forename: John L
authors.initials: JL
authors.lastname: Frattarelli
mesh_terms: D000328:Adult; D006063:Chorionic Gonadotropin / Q000097:blood; D015331:Cohort Studies; D015925:Cryopreservation / Q000379:methods; D010064:Embryo Implantation / Q000187:drug effects / Q000502:physiology*; D004624:Embryo Transfer / Q000379:methods*; D004717:Endometrium / Q000033:anatomy & histology / Q000187:drug effects; D004967:Estrogens / Q000627:therapeutic use; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists*; D006801:Humans; D007231:Infant, Newborn; D050498:Live Birth / Q000453:epidemiology*; D008297:Male; D008991:Monitoring, Physiologic; D011247:Pregnancy; D011374:Progesterone / Q000627:therapeutic use; D012044:Regression Analysis; D012189:Retrospective Studies
chemical_list: D006063:Chorionic Gonadotropin; D004967:Estrogens; D007987:Gonadotropin-Releasing Hormone; D011374:Progesterone