Elective single versus double embryo transfer: live birth outcome and patient acceptance in a prospective randomised trial.

The purpose of this study was to determine which strategy of embryo transfer has a better trade-off in live birth delivery rate versus multiple pregnancy considering patient acceptance: elective single embryo transfer (eSET) or elective double embryo transfer (eDET). In all, 199 women <38 years of age undergoing their first IVF treatment in a private centre were included in a prospective open-label randomised controlled trial. Patients were randomised into four groups: (1) eSET on Day 3; (2) eSET on Day 5; (3) eDET on Day 3; and (4) eDET on Day 5. Per patient, main analysis included acceptance of assigned group, as well as multiple and live birth delivery rates of the fresh cycle. Secondary analysis included the rates of subsequent cryotransfers and the theoretical cumulative success rate. Of 98 patients selected for eSET, 40% refused and preferred eDET. The live birth delivery rate after eDET was significantly higher after eDET versus eSET (65% vs 42%, respectively; odds ratio=1.6, 95% confidence interval 1.1-2.1). No multiple births were observed after eSET, compared with 35% after eDET. Although live birth delivery is higher with eDET, the increased risk of multiple births is avoided with eSET. Nearly half the patients refused eSET even after having been well informed about its benefits.