title: Elevated E2: oocyte ratio in women undergoing IVF and tubal ET. Correlation with a decrease in the implantation rate.
abstract: OBJECTIVE
  To investigate the influence of various estradiol (E2): oocyte ratios on reproductive outcome in women undergoing in vitro fertilization and tubal embryo transfer (IVF-TET).
  
  
  METHODS
  Two hundred seven women undergoing 251 IVF-TET cycles were recruited in this retrospective study. All the women received a flare-up gonadotropin releasing hormone agonist (GnRHa) protocol to achieve ovarian hyperstimulation. Oocyte retrieval was performed 34-36 hours after human chorionic gonadotropin (hCG) injection, followed by TET two days later.
  
  
  RESULTS
  An E2: oocyte ratio > or = 350 pg/mL had a higher E2 level (2,213 +/- 2,258 vs. 1,553 +/- 972 pg/mL, P < .05) and fertilization rate (77 +/- 23 vs. 64 +/- 23%, P < .001) but a lower oocyte number (4.8 +/- 4.7 vs. 7.6 +/- 4.8, P < .001) than in those with a ratio < 350 pg/mL. The pregnancy (17.9% vs. 32.8%, P = .03) and implantation (5.3% vs. 12.9%, P = .008) rates were significantly decreased in cycles with an E2: oocyte ratio > or = 350 pg/mL as compared to those with a ratio < 350 pg/mL.
  
  
  CONCLUSIONS
  IVF-TET cycles with an elevated E2: oocyte ratio correlated with lower pregnancy and implantation rates. The poor reproductive outcome possibly was due to the relatively high E2 concentration, which might have a detrimental effect on endometrial receptivity.
authors.affiliation: Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, National Taiwan University Hospital and College of Medicine, Taipei, Taiwan.
authors.forename: J H
authors.initials: JH
authors.lastname: Yang
authors.forename: H F
authors.initials: HF
authors.lastname: Chen
authors.forename: Y R
authors.initials: YR
authors.lastname: Lien
authors.forename: S U
authors.initials: SU
authors.lastname: Chen
authors.forename: H N
authors.initials: HN
authors.lastname: Ho
authors.forename: Y S
authors.initials: YS
authors.lastname: Yang
mesh_terms: D002064:Buserelin / Q000008:administration & dosage; D002452:Cell Count; D006063:Chorionic Gonadotropin / Q000008:administration & dosage; D010064:Embryo Implantation; D004624:Embryo Transfer; D004958:Estradiol / Q000097:blood*; D005260:Female; D005307:Fertilization in Vitro; D005640:Follicle Stimulating Hormone / Q000008:administration & dosage; D006801:Humans; D008596:Menotropins / Q000008:administration & dosage; D009865:Oocytes / Q000166:cytology*; D011247:Pregnancy; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D006063:Chorionic Gonadotropin; D004958:Estradiol; D008596:Menotropins; D005640:Follicle Stimulating Hormone; D002064:Buserelin