Received February 23, 2020
Accepted September 01, 2020

Background: The recent improvement of sequential media has refocused the attention on the role of human blastocyst in ART, not only because of its advantages but also because of the possible cancellation of embryo transfer when relying on blastocyst transfer only. Hence the idea of sequential transfer on day 3 and day 5, was proposed. Objective: To compare the pregnancy outcomes of sequential embryo transfer on day 3 and day 5, versus cleavage transfer on day 3 and blastocyst transfer on day 5 in cases of recurrent implantation failure. Patients and Methods: This was a prospective randomize trial in which 210 qualified patients with recurrent implantation failure undergoing IVF/ICSI were randomized into 3 groups, each group included 70 patients. Embryo transfer was performed in day 3 of first group, day 5 (blastocyst transfer) in the second group and sequential embryo transfer in day 3 and day 5 in the third group. Pregnancy outcomes of all the three groups were studied. Results: Clinical pregnancy and live birth rates were significantly higher in the sequential group than either day 3 or day 5 groups of embryo transfer in cases with recurrent implantation failure. Conclusion: Sequential embryo transfer in cases with recurrent implantation failure and adequate number of retrieved oocytes, is associated with higher implantation and clinical pregnancy rates and is advocated for patients having an adequate number of good quality embryos.