title: Comprehensive assessment of serum estradiol impact on selected physiologic markers observed during in-vitro fertilization and embryo transfer cycles.
abstract: OBJECTIVE
  This investigation assessed the effect of serum estradiol levels on outcomes of in-vitro fertilization and embryo transfer (IVF) cycles.
  
  
  METHODS
  This was a retrospective cohort study of 1123 IVF cycles comparing impact of estradiol (E(2)) levels on follicular development, fertilization, embryo quality, implantation, pregnancy rate, miscarriage rate, and selected obstetric complications.
  
  
  RESULTS
  We found high serum E(2) levels to be significantly associated with increased number of mature follicles and mature oocytes retrieved (p<0.01, for both). E(2) levels were also associated with more viable and good-quality embryos (p<0.01). There was no significant impact of E(2) on oocyte maturation, fertilization rate, embryo quality, or overall pregnancy rates. Moreover, high E(2) levels were significantly associated with higher implantation rates and reduced incidence of miscarriage (p<0.05, for both).
  
  
  CONCLUSIONS
  Within the safety range in clinical practice, our data demonstrate a generally positive effect of high serum E(2) on selected IVF parameters.
authors.affiliation: Department of Obstetrics and Gynecology, Prince of Wales Hospital, Shatin, Hong Kong SAR.
authors.forename: Grace Wing Shan
authors.initials: GW
authors.lastname: Kong
authors.forename: Lai Ping
authors.initials: LP
authors.lastname: Cheung
authors.forename: Christopher John
authors.initials: CJ
authors.lastname: Haines
authors.forename: Po Mui
authors.initials: PM
authors.lastname: Lam