Randomised clinical trial comparing elective single-embryo transfer followed by single-embryo cryotransfer versus double embryo transfer

Abstract

Objective: To analyze the impact of the eSET followed by single-embryo cryotransfer versus double embryo transfer in older women (<38 years) without taking into account embryo quality.

Study design: This is a prospective randomised clinical trial performed on 194 couples attempting a first IVF cycle in a Public Hospital in Spain. The women in Group 1 received eSET plus a single-embryo cryotransfer, and those in Group 2 received a double embryo transfer (DET).

Results: In the intention-to-treat analysis, the cumulative live birth delivery rate in the eSET group was similar to the results obtained for the DET group (45.2% vs. 41.8%; p = 0.60). The rate of multiple gestation was significantly lower in the eSET group than in the DET group (0% vs. 26.4%; p < 0.05). The findings obtained in the per-protocol analysis were similar to those obtained in the intention-to-treat analysis. The per-protocol analysis revealed no significant differences in the rate of implantation (29.8% in eSET vs. 29.7% in DET; p = 0.98), in cumulative pregnancy rates per transfer (49.1% in eSET vs. 46.9% in DET; p = 0.80) or in the cumulative live birth delivery rate (38.6% in eSET vs. 42.2% in DET; p = 0.69). In the cycles with eSET, there were no twin pregnancies (0% in eSET vs. 27.6 in DET; p < 0.05).

Conclusions: For women aged under 38 years with good prognosis, without taking embryo quality as a criterion for inclusion, an eSET policy can be applied, achieving acceptable cumulative clinical pregnancy rates and birth rates.

Trial registration: ClinicalTrials.gov NCT01909570.

Keywords: Clinical pregnancy rate; Elective single-embryo transfer; Vitrification.