Possible self correction of human trophectoderm (TE) cell lines during extended culture to 24 days

Abstract

and elected to undergo single thawed mosaic embryo transfer (STMET) after genetic counseling. When more than one mosaic embryo was available, embryo selection occurred following discussion between the patient, physician, and genetic counselor.RESULTS: A total of 587 frozen single embryo transfer cycles after IVF with NGS occurred during the selection period. STEET occurred in 569 cycles (mean age 35.8). Fifteen patients without euploid embryos elected to pursue STMET following genetic counseling (mean age 37.7). Nineteen mosaic embryos were thawed and transferred in 18 STMET cycles; one embryo did not survive thawing. Nine of 18 mosaic embryos (50.0%) implanted, as evidenced by the presence of a gestational sac, compared to 408/569 euploid embryos (71.7%; p¼0.06). The ongoing pregnancy/live birth rate for mosaic embryos was 4/18 (22.2%), which was significantly less than that for euploid embryos (358/569 or 62.9%; p¼0.001). The spontaneous abortion rate for mosaic embryos was 5/9 (55.6%), significantly higher than for euploid embryos (50/408 or 12.3%; p¼0.006). Of interest, all four embryos that resulted in ongoing pregnancies were identified as mosaic for segmental aneuploidies, while the remaining 12 embryos showed mosaicism for monosomies, trisomies, or segmental aneuploidies.