Elective single day 3 embryo transfer halves the twinning rate without decrease in the ongoing pregnancy rate of an IVF/ICSI programme.

Background: Data on the effect of elective single embryo transfer (eSET) on the total and multiple pregnancy rates of an IVF/ICSI programme are reported.

Methods And Results: A retrospective cohort analysis of eSET was carried out over a 4 year period. A total of 1559 cycles resulted in 1464 transfers; 299 transfers of one top quality embryo (20.