title: Prospective evaluation of endometrial thickness as a predictor of pituitary down-regulation after gonadotropin-releasing hormone analogue administration in an in vitro fertilization program.
abstract: OBJECTIVE
  To determine whether pituitary down-regulation after gonadotropin-releasing hormone analogue (GnRH-a) administration can be accurately predicted by transvaginal ultrasonographic measurement of endometrial thickness.
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  An IVF unit of an academic medical center.
  
  
  METHODS
  One hundred eighty-one patients undergoing 265 IVF-ET treatment cycles using GnRH-a in the long protocol.
  
  
  METHODS
  Serum concentrations of E2 were determined, and endometrial thickness was measured by transvaginal sonography. The accuracy of endometrial thickness for predicting pituitary down-regulation was calculated.
  
  
  RESULTS
  Pituitary down-regulation, defined as a serum E2 concentration of < or = 55 pg/mL, was achieved in 77% (204 of 265) of the cycles. An endometrial thickness of < or = 6 mm was found in 92.2% (188 of 204) of cycles in which down-regulation was achieved. An estradiol level of < or = 55 pg/mL was present in 95.9% (188 of 196) of cycles with endometrial thickness of < or = 6 mm.
  
  
  CONCLUSIONS
  A state of relative hypoestrogenism after GnRH-a administration, indicative of pituitary down-regulation, can be predicted with a high degree of accuracy by ultrasonographic measurement of endometrial thickness. Thus, routine testing for serum E2 concentration may be safely omitted. This may allow further simplification of IVF protocols and increase both cost-effectiveness and patients' convenience.
authors.affiliation: Department of Obstetrics and Gynecology, Kaplan Medical Center, (Affiliated with the Medical School of the Hebrew University and Hadassah, Jerusalem), Rehovot, Israel.
authors.forename: A
authors.initials: A
authors.lastname: Barash
authors.forename: A
authors.initials: A
authors.lastname: Weissman
authors.forename: M
authors.initials: M
authors.lastname: Manor
authors.forename: D
authors.initials: D
authors.lastname: Milman
authors.forename: A
authors.initials: A
authors.lastname: Ben-Arie
authors.forename: Z
authors.initials: Z
authors.lastname: Shoham
mesh_terms: D000328:Adult; D002064:Buserelin / Q000008:administration & dosage; D004717:Endometrium / Q000000981:diagnostic imaging*; D004958:Estradiol / Q000097:blood; D005260:Female; D005307:Fertilization in Vitro; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives*; D006801:Humans; D017274:Nafarelin / Q000008:administration & dosage; D010902:Pituitary Gland / Q000187:drug effects / Q000502:physiology*; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D017329:Triptorelin Pamoate / Q000008:administration & dosage; D014463:Ultrasonography
chemical_list: D017329:Triptorelin Pamoate; D017274:Nafarelin; D007987:Gonadotropin-Releasing Hormone; D004958:Estradiol; D002064:Buserelin