title: Premature progesterone elevation spares blastulation but not pregnancy rates in in vitro fertilization with coculture.
abstract: OBJECTIVE
  To clarify whether embryo development to the blastocyst stage may be affected by premature P elevation during controlled ovarian hyperstimulation (COH) for IVF-ET with embryo coculture.
  
  
  METHODS
  Retrospective study.
  
  
  METHODS
  Tertiary care infertility center.
  
  
  METHODS
  One hundred thirty-one women undergoing 153 IVF-ET cycles with embryo coculture.
  
  
  METHODS
  Patients underwent COH with GnRH agonist and hMG. Embryos were cocultured up to the blastocyst stage. According to plasma P levels on the day of hCG, two groups were defined: low P (P < or = 0.9 ng/mL; conversion factor to SI unit, 3.180) and high P (P > 0.9 ng/mL).
  
  
  METHODS
  Blastulation (number of blastocysts/number of noncavitating embryos x 100) and pregnancy rates (PRs).
  
  
  RESULTS
  Blastulation rates were similar in the low and high P groups (51% and 48%, respectively). Moreover, patients included in the high P groups achieved significantly lower clinical and ongoing PRs (12% versus 29% and 7% versus 25%, respectively).
  
  
  CONCLUSIONS
  The lack of difference in blastulation rates between the groups further supports the hypothesis that premature P elevation does not alter oocyte and embryo quality. Hence, the observed decrease in PRs is likely to reflect impaired endometrial receptivity in the high P group.
authors.affiliation: Hôpital Antoine Béclère, Clamart, France.
authors.forename: R
authors.initials: R
authors.lastname: Fanchin
authors.forename: A
authors.initials: A
authors.lastname: Hourvitz
authors.forename: F
authors.initials: F
authors.lastname: Olivennes
authors.forename: J
authors.initials: J
authors.lastname: Taieb
authors.forename: A
authors.initials: A
authors.lastname: Hazout
authors.forename: R
authors.initials: R
authors.lastname: Frydman
mesh_terms: D000328:Adult; D001755:Blastocyst / Q000502:physiology*; D018920:Coculture Techniques; D010064:Embryo Implantation; D005260:Female; D005307:Fertilization in Vitro; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists; D006801:Humans; D008596:Menotropins / Q000627:therapeutic use; D011247:Pregnancy; D018873:Pregnancy Rate; D011374:Progesterone / Q000097:blood*; D012189:Retrospective Studies
chemical_list: D007987:Gonadotropin-Releasing Hormone; D011374:Progesterone; D008596:Menotropins