title: The evolution of oocyte donation in China.
abstract: OBJECTIVE
  To review the experience with and clinical outcomes for recipients of embryos from oocytes donated under different regulatory standards in China. Initially, the oocytes were provided by one of the patient's consanguineous sisters. Then, the oocytes were obtained from another patient treated with assisted reproduction techniques (ART). Presently, oocytes thus produced are cryopreserved for at least 6months before transfer.
  
  
  METHODS
  The records from all women treated with ART at First Affiliated Hospital of Zhengzhou University since 2001 were reviewed and the pregnancy rates and clinical outcomes were determined for each of the 3 periods.
  
  
  RESULTS
  In the second period, the mean implantation and clinical pregnancy rates were significantly higher for the 22 oocyte recipients than for their donors. In the third period, the rates for the 56 recipients were compared with the 78 other regular ART patients fertilized with their own oocytes. There were 40 live births for 32 of the recipients over 28 cycles, and the rates of implantation and clinical pregnancy were much higher for the recipients than for the other ART patients (P<0.001).
  
  
  CONCLUSIONS
  Using freshly donated eggs yields a higher pregnancy rate but there is a risk of infectious disease. Using frozen oocytes can significantly decrease this risk but implantation rates are lower.
authors.affiliation: Center for Reproductive Medicine, First Affiliated Hospital of ZhengZhou University, Henan, China.
authors.forename: Fang
authors.initials: F
authors.lastname: Wang
authors.forename: Yingpu
authors.initials: Y
authors.lastname: Sun
authors.forename: Huijuan
authors.initials: H
authors.lastname: Kong
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.forename: Yingchun
authors.initials: Y
authors.lastname: Su
authors.forename: Yihong
authors.initials: Y
authors.lastname: Guo
mesh_terms: D000328:Adult; D002681:China; D015925:Cryopreservation; D004624:Embryo Transfer / Q000379:methods*; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D018587:Oocyte Donation / Q000379:methods*; D011247:Pregnancy; D011256:Pregnancy Outcome; D018873:Pregnancy Rate; D027724:Reproductive Techniques, Assisted / Q000706:statistics & numerical data*; D012189:Retrospective Studies