title: Hypoxia inducible factor and microvessels in peri-implantation endometrium of women with recurrent miscarriage.
abstract: To compare the expression of hypoxia inducible factor 1α (HIF1α) and micro-blood vessels in endometrium around the time of embryo implantation in women with recurrent miscarriage and fertile controls.
  
  
  
  Retrospective study.
  
  
  
  University hospitals.
  
  
  
  Sixty women: 24 with recurrent miscarriage and 36 with proven fertility.
  
  
  
  Endometrial biopsy samples obtained precisely 7 days after luteinization hormone (LH) surge in a natural cycle.
  
  
  
  Immunohistochemical analysis to determine expression of HIF1α and micro-blood vessels as identified by von Willebrand factor (vWF) in endometrium; semiquantitative analysis using H-score analysis of staining intensity for HIF1α in the luminal epithelium, glandular epithelium, and stroma, separately; number, diameter, and volume of vWF-positive endometrial micro-vessels as counted by Image J software.
  
  
  
  The luminal epithelial and stromal expression of HIF1α in women with recurrent miscarriage was higher than found in the fertile controls, with the change in the luminal epithelium reaching the highest statistical significance. There was no statistically significant difference in HIF1α expression in glandular epithelium between the two groups. An increased number as well as volume of micro-blood vessels was observed in women with recurrent miscarriage although the mean diameter of the micro-blood vessels did not statistically significantly differ between the two groups.
  
  
  
  We have found an aberrant expression of HIF1α and micro-vessel number and volume in the peri-implantation endometrium of women with recurrent miscarriage, suggesting that altered hypoxia and vascularization status may account for the endometrial contribution to recurrent miscarriage.
authors.affiliation: Department of Obstetrics and Gynaecology, Chinese University of Hong Kong, Shatin, Hong Kong, People's Republic of China.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Chen
authors.affiliation: Department of Obstetrics and Gynaecology, Shenzhen People's Hospital, Second Affiliated Hospital of Jinan University, Shenzhen, People's Republic of China.
authors.forename: Lingming
authors.initials: L
authors.lastname: Jiang
authors.affiliation: Department of Obstetrics and Gynaecology, Chinese University of Hong Kong, Shatin, Hong Kong, People's Republic of China; Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong; School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong.
authors.forename: Chi Chiu
authors.initials: CC
authors.lastname: Wang
authors.affiliation: Department of Obstetrics and Gynaecology, Chinese University of Hong Kong, Shatin, Hong Kong, People's Republic of China.
authors.forename: Jin
authors.initials: J
authors.lastname: Huang
authors.affiliation: Department of Obstetrics and Gynaecology, Chinese University of Hong Kong, Shatin, Hong Kong, People's Republic of China. Electronic address: tinchiu.li@gmail.com.
authors.forename: Tin Chiu
authors.initials: TC
authors.lastname: Li
mesh_terms: D000026:Abortion, Habitual / Q000175:diagnosis / Q000378:metabolism*; D000328:Adult; D010064:Embryo Implantation / Q000502:physiology*; D004717:Endometrium / Q000098:blood supply* / Q000378:metabolism*; D005260:Female; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000096:biosynthesis*; D007247:Infertility, Female / Q000175:diagnosis / Q000378:metabolism; D055806:Microvessels / Q000378:metabolism*; D012189:Retrospective Studies
chemical_list: C497442:HIF1A protein, human; D051795:Hypoxia-Inducible Factor 1, alpha Subunit
keywords: Angiogenesis; HIF1α; implantation; micro–blood vessels; recurrent miscarriage