Effect of the secretions from the IUD-bearing uterus on peri-implantation mouse embryos.

This study was performed to evaluate the effect of IUD-bearing uterine secretions on peri-implantation mouse embryo. 83% of blastocysts degenerated by 96 hr after co-culture with uterine fluids from the IUD-bearing uterus. This degeneration rate was contrasted to 78% after heat treatment (56 degrees C for 30 min) of the IUD-bearing uterine secretions. These results suggest that embryotoxic agents are present in the fluid of the IUD-bearing uterus, especially in the supernatant component and that these agents may be related to the presence of macrophage or a chemical mediator produced by macrophage.