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Published on: October 18, 2024
Assessment of early cleaving in vitro fertilized human embryos at the 2-cell stage before transfer improves embryo
D Sakkas1, G Percival, Y D'Arcy
1Assisted Conception Unit, Birmingham Women's Hospital, Edgbaston, Birmingham, United Kingdom. Denny.Sakkas@yale.edu
Objective:
To determine the most viable embryos for transfer.
Design:
Study 1: Preselection of early-cleaving 2-cell embryos for transfer. Study 2: Alternating weeks during which preselection was performed and not performed.
Setting:
ART program, Birmingham Women's Hospital, Birmingham, United Kingdom.
Patient(S):
Patients undergoing IVF or ICSI cycles with transfer on day 2.
Intervention(S):
Culture of all fertilized embryos.
Main Outcome Measure(S):
Number of fertilized embryos cleaving to the 2-cell stage on day 1, embryo quality, implantation rates, and pregnancy rates.
Result(S):
Patients with early-cleaving 2-cell embryos had significantly higher pregnancy and implantation rates (45 of 100 [45.0%] and 58 of 219 [25.5%], respectively) than did patients without early-cleaving 2-cell embryos (31 of 130 [23.8%] and 43 of 290 [14.8%], respectively). In weeks during which preselection was used, the overall pregnancy and implantation rates of the clinic improved.
Conclusion(S):
The presence of early-cleaving 2-cell embryos improves a patient's chance of achieving pregnancy. Use of more stringent embryo selection criteria can improve overall pregnancy rates.
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