Elsevier

Fertility and Sterility

Volume 106, Issue 2, August 2016, Pages 244-250
Fertility and Sterility

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Cleavage-stage or blastocyst transfer: what are the benefits and harms?

https://doi.org/10.1016/j.fertnstert.2016.06.029Get rights and content
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ET is a critical step in an assisted reproduction cycle. Over the past decade there has been an increasing trend to extending culture from cleavage-stage to blastocyst transfer. There has also been a trend to single ET and reporting the success of an assisted reproductive cycle as a cumulative live-birth rate after using both fresh and frozen embryos. There is low evidence that fresh blastocyst transfer is associated with improved live-birth rates compared with fresh cleavage-stage embryos. However, in the few studies that report cumulative pregnancy rates after fresh and frozen transfers, no significant difference was found. Cleavage-stage transfer is associated with greater numbers of embryos available for freezing, and blastocyst transfer is associated with increased number of cycles with no embryos to transfer. Further well-designed studies are warranted to evaluate the outcomes for blastocyst transfer including cumulative live-birth rate after fresh and frozen transfers, time to live birth, costs of the different transfer strategies, and perinatal mortality and severe perinatal morbidity.

Key Words

Embryo transfer
cleavage
blastocyst

Cited by (0)

D.G. has nothing to disclose. C.F. has nothing to disclose.