Predisposition to uterine microbial contamination in the guinea-pig following administration of mucolytic drugs and steroid hormones.

Using guinea-pigs as a mammalian model, the effects of bromhexine hydrochloride, ethinyloestradiol, norethisterone acetate and prednisolone acetate on uterine microbial status were determined. Those drugs known to decrease mucus viscoelasticity predisposed to the entry of vaginal bacteria into the uterus, probably due to reduction of the cervical mucus barrier. Norethisterone acetate, which increases cervical mucus viscoelasticity, reduced these effects. The effects produced by the steroid hormones were independent of their immunosuppressive effects. The results also suggest that prednisolone acetate may exert oestrogen-like actions on cervical mucus.