PURPOSE: To observe the differences in pregnancy rates (PRs), delivery rates, and abortion rates associated with frozen-embryo-transfer (FET)-based use of post-thawing embryos with different numbers of blastomeres. METHODS: 959 FET cycles and 361 successful FET cycles performed between January 2007 and December 2007. Compare the PRs and abortion rates in post-thawing embryos with 8 blastomeres (8c), 7c, 6c, 5c, 4c,and 3c. RESULTS: 1. The total PRs of post-thawing 8c, 7c, 6c, 5c, 4c, and 3c embryos were 44.1%, 41.0%, 34.4%, 23.8%, 12.5%, and 0%, respectively (p < 0.05). 2. The abortion rates for the transferred embryos of the 8c, 7c, 6c, 5c, and 4c groups were 17.92%, 19.35%, 27.69%, 24%, 20%, respectively (p < 0.05). CONCLUSION: The number of blastomeres in the post-thawing embryos is an important factor influencing the occurrence of pregnancy in FET procedures; however, the criterion that post-thawing embryos with 50% intact blastomeres will lead to pregnancy may not be valid.
PURPOSE: To observe the differences in pregnancy rates (PRs), delivery rates, and abortion rates associated with frozen-embryo-transfer (FET)-based use of post-thawing embryos with different numbers of blastomeres. METHODS: 959 FET cycles and 361 successful FET cycles performed between January 2007 and December 2007. Compare the PRs and abortion rates in post-thawing embryos with 8 blastomeres (8c), 7c, 6c, 5c, 4c,and 3c. RESULTS: 1. The total PRs of post-thawing 8c, 7c, 6c, 5c, 4c, and 3c embryos were 44.1%, 41.0%, 34.4%, 23.8%, 12.5%, and 0%, respectively (p < 0.05). 2. The abortion rates for the transferred embryos of the 8c, 7c, 6c, 5c, and 4c groups were 17.92%, 19.35%, 27.69%, 24%, 20%, respectively (p < 0.05). CONCLUSION: The number of blastomeres in the post-thawing embryos is an important factor influencing the occurrence of pregnancy in FET procedures; however, the criterion that post-thawing embryos with 50% intact blastomeres will lead to pregnancy may not be valid.
Authors: F D Houghton; K J Barr; G Walter; H-D Gabriel; R Grümmer; O Traub; H J Leese; E Winterhager; G M Kidder Journal: Biol Reprod Date: 2002-05 Impact factor: 4.285
Authors: Federica Di Guardo; A Racca; G Coticchio; A Borini; P Drakopoulos; S Mackens; H Tournaye; G Verheyen; C Blockeel; L Van Landuyt Journal: J Assist Reprod Genet Date: 2022-07-20 Impact factor: 3.357