Single Blastocyst Transfer: The Key to Reduce Multiple Pregnancy Rates Without Compromising the Live Birth Rate

J Hum Reprod Sci. 2017 Jul-Sep;10(3):201-207. doi: 10.4103/jhrs.JHRS_130_16.

Abstract

Background: Historically, to achieve higher pregnancy rates, multiple embryos were transferred after an in-vitro fertilisation (IVF). However, this practice is being reassessed, because it leads to multiple pregnancies that is known to cause adverse maternal and fetal outcomes.

Aim: To compare the pregnancy outcomes in fresh IVF or intracytoplasmic sperm injection (ICSI) cycles among women undergoing elective single blastocyst transfer (eSBT) vs. those undergoing double blastocyst transfer (DBT).

Settings and design: It is a retrospective data analysis of 582 patients undergoing fresh IVF/ICSI cycles performed from January 2012 to June 2015.

Materials and methods: Patients, who underwent IVF/ICSI and developed more than one blastocyst, were included in the study. Donor cycles were excluded from the study. All the embryos were cultured to blastocyst stage in sequential media followed by transfer of two blastocysts (DBT) or eSBT and cryopreservation of the remaining.

Statistical analysis: Statistical analysis was performed using chi square test.

Results: Out of 582 patients, in 149 patients one blastocyst was transferred and in 433 patients two blastocysts were transferred. There was no statistical difference in the biochemical pregnancy rate, clinical pregnancy rate and live birth rate in both the groups. Statistics demonstrated a significant drop in miscarriage rate in eSBT group. There was no incidence of twins in eSBT group, whereas twin birth rate per clinical pregnancy was 29.02% in DBT group.

Conclusion: Single blastocyst transfer is an effective method to reduce the risk of multiple births without compromising the pregnancy outcomes. Given the promising potential of vitrification; the remaining blastocyst can be cryopreserved.

Keywords: Cryopreservation; double blastocyst transfer; elective single blastocyst transfer; in vitro fertilisation; miscarriage; multiple pregnancy.