title: Uterine cavity shape and the best site for embryo transfer.
abstract: OBJECTIVE
  To determine the best site for embryo placement in uterine cavities of varying shapes.
  
  
  METHODS
  In this prospective investigation, 638 embryo transfers were allocated to two groups: for group 1 (n=558) embryos were transferred into uterine cavities of normal shape; for group 2 (n=80) embryos were transferred into uterine cavities of abnormal shape. The uterine cavity was divided into 3 equal regions: upper, middle, and lower. Pregnancy outcomes for placements in each region were compared within and between the 2 groups.
  
  
  RESULTS
  No significant differences were found in rates of pregnancy or implantation among the 3 regions in group 1. In contrast, the implantation rate in group 2 was highest when embryos were placed in the middle region of the uterine cavity: 28.8% compared with 6.8% and 8.3% for the upper and lower regions, respectively (P<0.05).
  
  
  CONCLUSIONS
  For the normal uterine cavity, pregnancy outcomes do not depend on embryo placement. However, for uterine anomalies, embryo placement in the middle region of the uterine cavity gave the best outcome.
authors.affiliation: Center for Reproductive Medicine, Department of Obstetrics and Gynecology, First Affiliated Hospital of Zhengzhou University, Zhengzhou Henan, China. syp2008@vip.sina.com
authors.forename: Yingpu
authors.initials: Y
authors.lastname: Sun
authors.forename: Lanlan
authors.initials: L
authors.lastname: Fang
authors.forename: Yingchun
authors.initials: Y
authors.lastname: Su
authors.forename: Yihong
authors.initials: Y
authors.lastname: Guo
mesh_terms: D000328:Adult; D004624:Embryo Transfer / Q000379:methods*; D005260:Female; D006801:Humans; D011247:Pregnancy; D011256:Pregnancy Outcome; D018873:Pregnancy Rate; D011446:Prospective Studies; D014599:Uterus / Q000033:anatomy & histology*; D055815:Young Adult