title: Endometrial dating and determination of the window of implantation in healthy fertile women.
abstract: OBJECTIVE
  To reassess endometrial morphological criteria of normality identifying the best morphological and molecular "implantation window" indicators in normal women.
  
  
  METHODS
  Prospective clinical study.
  
  
  METHODS
  Assisted reproductive unit.
  
  
  METHODS
  Fourteen healthy volunteers.
  
  
  METHODS
  Blood sampling for LH, E(2), and progesterone (P4) determinations. Daily vaginal ultrasounds. Two endometrial biopsies per volunteer, 7 days apart, during luteal phase.
  
  
  METHODS
  Endometrial dating, pinopodes formation, immunohistochemical determination of integrins (alphavbeta3, alpha4beta1), leukemia inhibitory factor (LIF), interleukin-1 receptor type I (IL-1R tI), mouse ascites Golgi (MAG), the transmembrane mucin (MUC-1), and P4 receptor expression.
  
  
  RESULTS
  In 26 of 28 biopsies observers agreed; in two biopsies there was a discrepancy (difference of 72 hours). With use of LH peak, 24 of 26 samples were in phase, and 2 were 3 days behind. Pinopodes appeared on days 20-21 and persisted through day 28 in small groups or larger areas. beta3 Integrin was highly expressed in luminal and glandular epithelium from day 22 through 28; 48 hours thereafter pinopodes appeared. alpha4 Subunit exhibited luminal epithelium reaction positivity on days 22-23 and glands on days 18-23. LIF and IL-1R tI showed weak, erratic expression. MAG antibodies showed luminal epithelium expression up to day 22 and glands up to day 25. MUC-1 showed positivity during the whole luteal phase. P4 receptors were positive through day 20 and at the end of the luteal phase.
  
  
  CONCLUSIONS
  The three most cited markers that frame the window of implantation do not correlate in our material. Pinopodes are present from day 20 on; beta3 and alpha4 integrin subunits indicate a window opening on days 22-23.
authors.affiliation: University of Buenos Aires, Buenos Aires, Argentina.
authors.forename: A A
authors.initials: AA
authors.lastname: Acosta
authors.forename: L
authors.initials: L
authors.lastname: Elberger
authors.forename: M
authors.initials: M
authors.lastname: Borghi
authors.forename: J C
authors.initials: JC
authors.lastname: Calamera
authors.forename: H
authors.initials: H
authors.lastname: Chemes
authors.forename: G F
authors.initials: GF
authors.lastname: Doncel
authors.forename: H
authors.initials: H
authors.lastname: Kliman
authors.forename: B
authors.initials: B
authors.lastname: Lema
authors.forename: L
authors.initials: L
authors.lastname: Lustig
authors.forename: S
authors.initials: S
authors.lastname: Papier
mesh_terms: D000328:Adult; D010064:Embryo Implantation; D004717:Endometrium / Q000033:anatomy & histology / Q000502:physiology*; D004958:Estradiol / Q000097:blood; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D006056:Golgi Apparatus / Q000276:immunology; D006131:Growth Inhibitors / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D039041:Integrin alpha4beta1; D016023:Integrins / Q000378:metabolism; D015850:Interleukin-6; D053605:Leukemia Inhibitory Factor; D007986:Luteinizing Hormone / Q000097:blood; D008222:Lymphokines / Q000378:metabolism; D008597:Menstrual Cycle / Q000502:physiology*; D008855:Microscopy, Electron, Scanning; D009077:Mucins / Q000378:metabolism; D011446:Prospective Studies; D017472:Receptors, Interleukin-1 / Q000378:metabolism; D053573:Receptors, Interleukin-1 Type I; D016201:Receptors, Lymphocyte Homing / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D019030:Receptors, Vitronectin / Q000378:metabolism; D012016:Reference Values
chemical_list: D006131:Growth Inhibitors; D039041:Integrin alpha4beta1; D016023:Integrins; D015850:Interleukin-6; C507837:LIF protein, human; D053605:Leukemia Inhibitory Factor; C507838:Lif protein, mouse; D008222:Lymphokines; D009077:Mucins; D017472:Receptors, Interleukin-1; D053573:Receptors, Interleukin-1 Type I; D016201:Receptors, Lymphocyte Homing; D011980:Receptors, Progesterone; D019030:Receptors, Vitronectin; D004958:Estradiol; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone