Single embryo transfer (SET) using graduated embryo score (GES) and soluble human leukocyte antigen-G (HLA-G): an update

Abstract

OBJECTIVE: We presented preliminary SET data in 2007 showing a 65% delivery rate from single blastocyst transfer in a small group of patients with a GES and HLA-G+ embryo. This work updates our on-going experience with single embryo transfer among a larger group of patients. DESIGN: Retrospective. MATERIALS AND METHODS: From 2004-2009 a single physician performed 1679 embryo transfers into 806 different patients. All embryos were scored using GES, which uses early developmental milestones to generate a score on day 3 of culture. Embryos scoring 70+ were considered positive. Since 2005, discarded media droplets on day 2 were evaluated for HLA-G secretion in patients not doing PGD with more than 5 embryos. An OD in the range of 0.148-0.210 was considered positive. Main outcome measures: delivery, multiple gestation rates. RESULTS: In all, 248 (15%) embryo transfers were SET. Of these 169 (68%) were GES+ and 79 were GES negative. Of the GES+ SET, 103 (61%) were day 5 ET and 66 (39%) were day 3 ET. The overall delivery rate from SET was 24% (60/248). Among GES+ SET the delivery rate was 31% (52/169), compared to 10% (8/79) if GES negative. Of the GES+ SET, delivery rates were 42% (43/103) from day 5 ET and 14% (9/66) from day 3ET. Of the 103 GES+ day 5 SET, HLA-G data was available for 65 (63%). Among GES+ HLA-G+ day 5 SET the delivery rate was 57% (29/51) compared to 21% (3/14) among GES+ HLA-G negative day 5 SET. There was 1 set of monozygotic twins. CONCLUSION: In this update, we reconfirm the benefits of GES and HLA-G for evaluating embryos. Because SET has been difficult for our patients to accept, only a small portion of the total embryos transferred in this period were SET. However, these data show SET does achieve high success rates without significant risk of multiple gestations and the number of patients choosing SET will certainly rise over time. Since 2006 SET has routinely been recommended to our patients if the embryos meet GES/ HLA-G criteria. Increasing confidence with SET has led to increased acceptance.