Training of providers in embryo transfer: What is the minimum number of transfers required for proficiency?

Background: Embryo transfer represents one of the most critical procedures in the practice of assisted reproduction. The objective of this study was to identify retrospectively the minimum number of embryo transfers required to train providers properly in this skill. Methods and results: The study group consisted of 204 patients who received embryo transfers between January 1996 and March 2000 in a university-based programme of assisted reproduction. The main outcome measure was clinical pregnancies per embryo transfer. Five Fellow trainees performed a total of 204 embryo transfers for an overall pregnancy rate of 45.5% per embryo transfer (93/204). In comparison, the programme pregnancy rate per transfer for experienced providers was 47.3% (560/1179). A chronological graph of each individual trainee's experience for the first 50 embryo transfers performed suggested a lower initial pregnancy rate for three of the five trainees. To determine whether a learning curve might exist, results of the first 25 transfers were compared as a subgroup with the second 25 transfers. Pregnancy rates were lower for the 1-25 transfer subgroup than in the 26-50 subgroup for three of the five Fellow trainees, although the difference was not statistically significant. Conclusion: Clinical pregnancy rates of Fellow-in-training were indistinguishable statistically from those of experienced staff by 50 transfers.