A Comparative Analysis Between Day 2 and Day 3 Embryo Transfer in IVF/ICSI: A Retrospective Cross-Sectional Study

Although the fertilization and cleavage rate of implanted embryos is about 70%-90% in most patients, only a small number of embryos grown in vitro have the potential to implant. This indicates that many factors are responsible for a successful implantation, including obtaining viable embryos for transfer. This study aimed to examine the clinical results of pregnancy and implantation rates between day 2 and day 3 embryo transfer (ET) in women under the age of 40 experiencing fresh intracytoplasmic sperm injection-embryo transfer (ICSI-ET) cycles.
In a retrospective study, a total of 284 ETs were examined from March 2013 to December 2014. The transfer was done according to physician’s preference, patient characteristics or number of embryos available.
The data suggested that clinical (35.4% vs. 28.9%, P = 0.26) or ongoing pregnancy (32.5% vs. 23.7%, P = 0.11) or implantation rate (0.267 ± 0.2 vs. 0.216, P = 0.09) was slightly better and the miscarriage rate (3.1% vs. 7%, P = 0.153) was slightly lower on day 3 ET vs. day 2, however, this difference was not significant. Although most of the baseline characteristics were similar between groups, the number of high-quality embryos (5.29 ± 3.9 vs. 4.47 ± 3.05, P = 0.011) and average embryo cleavage score (2.85 ± 0.4 vs. 2.25 ± 0.3, P A similar clinical outcome between ET performed on days 2 and 3 in women younger than 40 years undergoing fresh ICSI-ET is suggested by the results of this study.