Double (consecutive) transfer of early embryos and blastocysts: aims and results

Objective: The aim of this study was to evaluate the consecutive transfer approach of early embryos and blastocyst(s). Design: Case-control study. Setting: Public assisted reproduction technology unit. Patient(s): The study population consisted of three groups. In Group 1, a double transfer was performed on 136 consecutive women, that is, a standard transfer of embryos on day 2 or 3, and a second transfer of a blastocyst(s). In Group 2, an early transfer of only two embryos and a second transfer of one blastocyst were performed on 29 women from group 1 who had more than three high-quality embryos available for early transfer. In Group 3, a single early transfer was performed on 139 consecutive women who received three high-quality embryos (controls). Intervention(s): Early embryo transfer, extended culture of the spare embryos, and a second transfer of a blastocyst(s). Main Outcome Measure(s): Implantation and pregnancy rates. Result(s): No differences were detected among the three groups in either pregnancy or implantation rates (pregnancy: 36.8%, 41.4%, and 37.3%, respectively; implantation: 14.6%, 19.9%, and 19.8%, respectively). Conclusion(s): The double (consecutive) transfer of early embryos and blastocyst(s) does not offer any advantage over the traditional early transfer. This may be from the adverse effect of the second transfer on the implantation process. (Fertil Steril(R) 2000;74:936-30. (C) 2000 by American Society for Reproductive Medicine.)