Separate transfer of two frozen-thawed embryos reduces multiple gestations in assisted reproductive technology

Aim: In assisted reproductive technology (ART), there are different opinions regarding how an embryo should be transferred to the uterus. For double embryo transfer (DET) cycles in particular, there is no consensus regarding the appropriate embryo transfer (ET) method. Therefore, the present authors developed a novel ET method called separated (s-DET); with this method, two embryos are transferred to separate settings. The authors evaluated and compared pregnancy outcomes of s-DET and conventional DET (c-DET). Materials and Methods: In this prospective cohort study, 129 patients underwent separated ET. One hundred fifty-two patients underwent c-DET, which involves transferring two embryos together. All patients underwent ET of two frozen-thawed embryos. Results: The clinical pregnancy and implantation rates of the s-DET group were 20.9 % and 10.4 %, respectively; these rates were similar to those of the conventional DET group (26.3 % and 16.1 %, respectively). However, the multiple gestation rate of the D-DET group (0.0 %) was significantly lower than that of the conventional double ET group (22.5 %; p = 0.006). Conclusions: s-DET might make ART safer and decrease multiple gestations resulting from DET cycles.