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Published on: October 18, 2024
Effectiveness of two-step (consecutive) embryo transfer in patients who have two embryos on day 2: comparison with
Sakae Goto1, Masahide Shiotani, Masaru Kitagawa
1Hanabusa Women's Clinic, Kobe, Hyogo, Japan. gotoms@tcn.zaq.ne.jp
Objective:
To evaluate the effectiveness, for patients who have only two embryos on day 2, of a two-step (consecutive) embryo transfer (ET) procedure in which a cleaved embryo is transferred on day 2 and a single blastocyst is transferred on day 5.
Design:
Observational comparative study.
Setting:
Private IVF clinic.
Patient(S):
Ninety two-step ET cycles were performed in patients who had two embryos on day 2 (two-step group). Ninety day-2 ET cycles were performed in age- and infertility-matched patients who had two embryos on day 2 (control group).
Intervention(S):
Cleaved-ET, extended culture of one embryo, and a second transfer of a blastocyst.
Main Outcome Measure(S):
Implantation and pregnancy rates.
Result(S):
The pregnancy and implantation rates in the two-step group (respectively 33.3% and 17.2%) were significantly higher than those in the control group (18.9% and 9.4%). Thirty-nine of the patients in the two-step group (43.3%) could not proceed to the second step of ET because no viable blastocyst could be obtained, but four of them conceived anyway.
Conclusion(S):
Taking advantage of both day-2 ET and blastocyst transfer, two-step ET may be an effective option for ET in patients who have an insufficient number of embryos.
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