Comparison between sequential transfer vs. day 3 and day 5 frozen embryo transfer in IVF patients

Background: Sequential embryo transfer is when both cleavage-stage embryo is transferred on day 3 and blastocyst is transferred on day 5, sequentially in the same cycle. This has been suggested for increasing embryo implantation rate. Sequential transfer gives benefit of both day 3 as well as day 5 transfer in the same cycle, giving better outcome in patients suffering infertility. This study compares the implantation rates in sequential transfer vs Day 3 and day 5 transfers. Methods: This multi-centric study is a retrospective study conducted over a period of one year at D. Y. Patil Fertility Centre, Navi Mumbai. Total of 432 transfers were conducted in patients, out of which 262 were Day 3 or cleavage stage embryo transfer, 109 were Day 5 or blastocyst embryo transfer and 61 were sequential embryo transfer. Results: Day 3 transfer group had the clinical pregnancy rate of 52.67%, whereas day 5 transfer group had 60.55% of clinical pregnancy positive cases. Sequential embryo transfer had implantation rate of 60.66%, which was slightly higher than day 5 (60.55%) and day 3 (52.67%) implantation rates. Conclusions: Sequential transfer has marginally increased rate of implantation and clinical pregnancy when compared to day 5 and day 3 transfers.