Case report: Two successful pregnancies following the transfer of re-vitrified human day 7 blastocysts developed from vitrified cleaved embryos

PURPOSE: To report successful pregnancies after the transfer of re-vitrified human day 7 blastocysts developed from vitrified cleaved embryos. METHODS AND RESULTS: A total of five day 7 blastocysts developed from vitrified cleaved embryos were re-vitrified and re-warmed. All of five re-vitrified day 7 blastocysts (100%) survived after warming and were transferred to three patients. Two of the women became clinically pregnant. Of these women, one woman delivered a healthy baby and the other pregnancy is ongoing at 26 weeks of gestation. CONCLUSIONS: This is the first report of successful pregnancies after the transfer of re-vitrified human day 7 blastocysts developed from vitrified cleaved embryos.