Penetration of bacteria and spermatozoa into bovine cervical mucus.

It has been reported that bacteria may attach to motile spermatozoa, be carried through the cervix and uterus to the fallopian tubes, and cause acute salpingitis. In an attempt to mimic these conditions in vitro, we incubated Escherichia coli, Streptococcus faecalis, Pseudomonas aeruginosa, and Staphylococcus aureus with motile spermatozoa which then were allowed to migrate through a capillary filled with bovine cervical mucus. After satisfactory sperm migration through the mucus, the capillaries were broken and cultured at different distances from the original insemination site. Mucus fractions in proximity to bacterial inocula grew varying amounts of the pathogens. More distal fractions of mucus columns were generally culture-negative even though they contained motile sperm which had been exposed to bacteria. Migration of spermatozoa exposed to bacteria through bovine cervical mucus did not result in enhanced bacterial penetration.