OBJECTIVE: To review the outcomes of frozen-thawed embryo transfer cycles. DESIGN. Retrospective review. SETTING: Tertiary assisted reproduction centre, Hong Kong. PATIENTS: Subfertile patients undergoing frozen-thawed embryo transfer between July 2005 and December 2007. MAIN OUTCOME MEASURES: Clinical and ongoing pregnancy rates. RESULTS: A total of 983 frozen-thawed embryo transfer cycles performed during the study period were reviewed. The clinical pregnancy and ongoing pregnancy rates were 35% and 30%, respectively. Factors associated with successful outcome included younger maternal age (<=35 years) and 4 or more blastomeres at replacement, but not the method of insemination, the cause of subfertility, or the type of frozen-thawed embryo transfer cycle. The overall multiple pregnancy rate was 18%. For cycles with a single embryo replaced, embryos having 4-cell or higher stages at replacement gave an ongoing pregnancy rate of 25%, whereas those with less than 4 cells had a significantly lower ongoing pregnancy rate of 5% only. Blastomere lysis after thawing significantly reduced the clinical pregnancy and ongoing pregnancy rates of cycles with one embryo replaced. CONCLUSIONS: Clinical pregnancy and ongoing pregnancy rates of frozen-thawed embryo transfer cycles were 35% and 30%, respectively. Higher pregnancy rates were associated with younger maternal age (<=35 years), blastomere numbers of 4 or more, and no blastomere lysis after thawing.
OBJECTIVE: To review the outcomes of frozen-thawed embryo transfer cycles. DESIGN. Retrospective review. SETTING: Tertiary assisted reproduction centre, Hong Kong. PATIENTS: Subfertile patients undergoing frozen-thawed embryo transfer between July 2005 and December 2007. MAIN OUTCOME MEASURES: Clinical and ongoing pregnancy rates. RESULTS: A total of 983 frozen-thawed embryo transfer cycles performed during the study period were reviewed. The clinical pregnancy and ongoing pregnancy rates were 35% and 30%, respectively. Factors associated with successful outcome included younger maternal age (<=35 years) and 4 or more blastomeres at replacement, but not the method of insemination, the cause of subfertility, or the type of frozen-thawed embryo transfer cycle. The overall multiple pregnancy rate was 18%. For cycles with a single embryo replaced, embryos having 4-cell or higher stages at replacement gave an ongoing pregnancy rate of 25%, whereas those with less than 4 cells had a significantly lower ongoing pregnancy rate of 5% only. Blastomere lysis after thawing significantly reduced the clinical pregnancy and ongoing pregnancy rates of cycles with one embryo replaced. CONCLUSIONS: Clinical pregnancy and ongoing pregnancy rates of frozen-thawed embryo transfer cycles were 35% and 30%, respectively. Higher pregnancy rates were associated with younger maternal age (<=35 years), blastomere numbers of 4 or more, and no blastomere lysis after thawing.
Authors: Hang Wun Raymond Li; Vivian Chi Yan Lee; Estella Yee Lan Lau; William Shu Biu Yeung; Pak Chung Ho; Ernest Hung Yu Ng Journal: J Assist Reprod Genet Date: 2013-12-14 Impact factor: 3.412
Authors: Joyce Chai; Vivian Chi-Yan Lee; Tracy Wing-Yee Yeung; Hang Wun Raymond Li; Raymond Wun-Hang Li; Pak-Chung Ho; Ernest Hung-Yu Ng Journal: PLoS One Date: 2015-03-06 Impact factor: 3.240
Authors: Hang Wun Raymond Li; Vivian Chi Yan Lee; Estella Yee Lan Lau; William Shu Biu Yeung; Pak Chung Ho; Ernest Hung Yu Ng Journal: PLoS One Date: 2014-10-14 Impact factor: 3.240
Authors: Hang Wun Raymond Li; Vivian Chi Yan Lee; Estella Yee Lan Lau; William Shu Biu Yeung; Pak Chung Ho; Ernest Hung Yu Ng Journal: PLoS One Date: 2013-04-23 Impact factor: 3.240