The effect of maternal cytomegalovirus infection on preimplantation development in the mouse

Mice were inoculated with murine cytomegalovirus at 14 and 7 days before and 1 and 4 days after mating. The effects of maternal infection on early pregnancy were investigated. Inoculation 7 days before and 1 day after mating, i.e. around ovulation and implantation, significantly reduced pregnancy rate. Embryos in these females were developmentally retarded, perhaps because of the inflammatory effect of the infection on the genital tract. Retarded embryos developed normally when cultured.