Influence of insemination on the implantation of transferred rat blastocysts

Embryo transfer probably produces a lower incidence of implantation than the physiological incidence despite all other factors seeming similar. The only factor known to be present physiologically and absent in embryo transfer is the presence of sperm in the uterine cavity. Implantation and decidualization are often considered a modified form of inflammatory reaction. Semen contains factors which excite an inflammatory response. This project attempted to determine whether insemination would affect the implantation rate of transferred blastocysts in the rat. The figures showed a significantly increased implantation rate after insemination at day 4 of pseudopregnancy as compared to controls.