The Pregnancy Outcomes of Day 2 versus Day 3 Embryo Transfer: A Cross-Sectional Study

Background The objective was to evaluate whether extending the embryo culture period from 2 to 3 days would yield a more optimal selection of viable embryos, thereby increasing the pregnancy rat. MaterialsAndMethods We have retrospectively analyzed pregnancy rates in the patients who had embryo transfer either on day 2 (582 patients) or on day 3 (387 patients) post-insemination over a 10-month period. The relationship between the quality score of day 2 and day 3 embryos and their respective pregnancy rates was also analyzed. Results The demographic and clinical characteristics were similar in both groups. Embryos transferred on day 2 or day 3, were similar morphologically& we found no difference in the distribution of grades between patients who became pregnant and those who failed to become pregnant. Pregnancy rates were slightly higher in patients who had embryo transfer on day 3 (40.72%) than patients who had .transferred on day 2 (38.96%), but this difference was not significant proportion of embryos with 2-3 cells, four cells, and 5-7 cells, which selected for transfer, showed significant difference between day 2 and day 3 (p