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Day 4 versus day 3 embryo transfer: a prospective study of clinical outcomes
Konstantinos Pantos1, Evangelos Makrakis, Margaret Chronopoulou
1Center for Human Reproduction, Genesis Athens Clinic, Athens, Greece.
Objective:
To compare the clinical outcomes after day 4 or day 3 embryo transfers in controlled ovarian hyperstimulation-IVF/intracytoplasmic sperm injection (ICSI) cycles.
Design:
Prospective randomized study.
Setting:
Center for Human Reproduction, 'Genesis Athens' Clinic (private gynecological and surgical clinic), Athens, Greece.
Patient(S):
Three hundred fifty women with primary infertility and indication for IVF/ICSI treatment. Patients were randomly allocated to day 4 or day 3 embryo transfer.
Intervention(S):
Controlled ovarian hyperstimulation, oocyte retrieval, IVF/ICSI, embryo transfer.
Main Outcome Measure(S):
Implantation rate; clinical, ongoing, and multiple pregnancy rates.
Result(S):
A trend toward higher clinical and ongoing pregnancy rates was noted after day 4 embryo transfers. Implantation and multiple pregnancy rates were comparable after day 4 or day 3 embryo transfers.
Conclusion(S):
The transfer of day 4 embryos in IVF/ICSI cycles may result in favorable implantation and pregnancy rates which are at least comparable to those after the transfer of day 3 embryos.
