Day 4 versus day 3 embryo transfer: a prospective study of clinical outcomes.
OBJECTIVE
To compare the clinical outcomes after day 4 or day 3 embryo transfers in controlled ovarian hyperstimulation-IVF/intracytoplasmic sperm injection (ICSI) cycles.


METHODS
Prospective randomized study.


METHODS
Center for Human Reproduction, 'Genesis Athens' Clinic (private gynecological and surgical clinic), Athens, Greece.


METHODS
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.


METHODS
Controlled ovarian hyperstimulation, oocyte retrieval, IVF/ICSI, embryo transfer.


METHODS
Implantation rate; clinical, ongoing, and multiple pregnancy rates.


RESULTS
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.


CONCLUSIONS
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.
Pantos
Konstantinos
K
Center for Human Reproduction, Genesis Athens Clinic, Athens, Greece.
Makrakis
Evangelos
E
Chronopoulou
Margaret
M
Biba
Maria
M
Perdikaris
Anastasios
A
Dafereras
Alex
A
D000328:Adult; D046149:Embryo Culture Techniques; D010064:Embryo Implantation; D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D007246:Infertility / Q000628:therapy*; D010062:Ovulation Induction; D011247:Pregnancy; D018873:Pregnancy Rate; D011446:Prospective Studies; D020554:Sperm Injections, Intracytoplasmic; D013997:Time Factors; D016896:Treatment Outcome