Effect of Sequential Embryo Transfer on Pregnancy Rate in Patients With Repeated Implantation Failure

Background: inspite of the most investigation about fertility and fertilization, more than 50% of the embryos transferred on microinjection (IVF / ICSI) cycles can not be implanted. A diversity of treatment plans and protocol modifications are proposed for low responders . However, patients with repeat implantation failure (RIF) history inspite of good quality embryos and endometrium, have become a medical challenge for treatment centers. One of the reasons of RIF is the disaccord of timing between the embryo and endometrium, which some researchers believe that the sequential transfer of embryos in the Cleavage and Blastocyst stages can improve pregnancy rate in RIF patients. Objective: The purpose of this study was to compare IVF outcome following sequential embryo transfer to compare pregnancy rate in RIF patients who their embryos were transferred sequentially on day 3 and on day 5 with RIF patient’s that had conventional day 3 or day5 transfer as control groups. Methods: This prospective study was performed in Novin infertility treatment center from June 2015 to Agust 2017. 101 patients with RIF who underwent sequential embryo transfer (on day 3 and on day 5) were analysed on clinical pregnancy rate. 219 patient’s with RIF during the same time period who did not have sequential transfer ( cleavage transfer : 121, blastocyst transfer : 98) were used as controls.Results: The variables such as number of embryo transfer, male factor, tubal factor, etc. were the same in the women surveyed. The results showed that the clinical pregnancy rate was statistically significantly higher in the sequential embryo transfer (ET) group than the day3 group (58.6% vs. 42.5%), while the clinical pregnancy rates of he sequential ET group and blastocyst groups were 58.6% vs. 54.7%, that there was no statistically significant difference. Conclusion: A sequential transfer in ART cycles for patients with RIF is a very positive approach if the goal is to increase pregnancy and implantation rate, Particularly, pregnancy outcomes have improved compared to day 3 transfer. Priority sequential transfer cycles to blastocyst transfer cycle of not losing the cleavage step in the case of embryos that have lack of blastocyst progression.

Keywords:

sequential transfer , RIF , pregnancy rate , day3 transfe