Human Uterine Lavage: First Live Births from In Vivo Conceived Genetically Screened Blastocysts.

The overall goal of this research was to develop a procedure that would allow collection of naturally conceived human embryos and compare them to embryos that result from the standard process of in vitro fertilization (IVF). IVF is a procedure where eggs are surgically removed from the ovaries and fertilized with sperm in a laboratory. Embryos from IVF are cultured for 3­7 days before they are placed back into a woman's uterus to establish a pregnancy. Uterine lavage is a different procedure where the sperm fertilizes an egg in the normal process of conception and the uterus is rinsed with fluid to recover the embryo before implantation. The embryos reported in this study were the first to be obtained in over 30 years owing to many improvements in the overall uterine lavage procedure. Until our initial study findings reported in 2020, the vast majority of information on embryo development was based on embryos fertilized and cultured in a laboratory. Our prior report of embryos obtained by uterine lavage compared with IVF embryos from the same women demonstrated a significantly better appearance of the embryos recovered by lavage. This current report documents the first live births from these genetically screened naturally conceived human embryos. The live births provide evidence that uterine lavage allows ready access to normal embryos without performing the surgical procedure IVF. Owing to the simplicity of uterine lavage, the procedure may improve access to genetic testing of embryos before pregnancy.