title: Quantifying the changes in endometrial vascularity throughout the normal menstrual cycle with three-dimensional power Doppler angiography.
abstract: BACKGROUND
  We used three-dimensional power Doppler angiography (3D-PDA) to examine the periodic changes in endometrial and subendometrial vascularity during the normal menstrual cycle in 27 women without obvious menstrual dysfunction or subfertility.
  
  
  METHODS
  3D-PDA was performed on alternate days from day 3 of the cycle until ovulation and then every 4 days until menses. Virtual organ computer-aided analysis and shell-imaging were used to define and to quantify the power Doppler signal within the endometrial and subendometrial regions producing indices of their relative vascularity.
  
  
  RESULTS
  Both the endometrial and subendometrial vascularization index (VI) and vascularization flow index (VFI) increased during the proliferative phase, peaking approximately 3 days prior to ovulation (P < 0.001) before decreasing to a nadir 5 days post-ovulation (P < 0.001). Thereafter, both vascular indices gradually increased during the transition from early to mid-secretory phase. The flow index (FI) showed a similar pattern but with a longer nadir post-ovulation. Smoking was associated with a significantly lower VI and VFI. The FI was significantly lower in women aged > or = 31 years and significantly higher in parous patients.
  
  
  CONCLUSIONS
  Endometrial vascularity, as assessed by 3D-PDA, varies significantly during the menstrual cycle and is characterized by a pre-ovulatory peak and post-ovulatory nadir during the peri-implantation window.
authors.affiliation: Academic Division of Reproductive Medicine, School of Human Development, University of Nottingham, UK. nick.fenning@nottingham.ac.uk
authors.forename: N J
authors.initials: NJ
authors.lastname: Raine-Fenning
authors.forename: B K
authors.initials: BK
authors.lastname: Campbell
authors.forename: N R
authors.initials: NR
authors.lastname: Kendall
authors.forename: J S
authors.initials: JS
authors.lastname: Clewes
authors.forename: I R
authors.initials: IR
authors.lastname: Johnson
mesh_terms: D000328:Adult; D000375:Aging; D004717:Endometrium / Q000098:blood supply*; D004958:Estradiol / Q000097:blood; D005260:Female; D005498:Follicular Phase; D006801:Humans; D008183:Luteal Phase; D008597:Menstrual Cycle; D010060:Ovulation; D010298:Parity; D011374:Progesterone / Q000097:blood; D018608:Ultrasonography, Doppler / Q000379:methods*
chemical_list: D011374:Progesterone; D004958:Estradiol