[Pharmacological studies of intravaginally applied dehydroepiandrosterone sulfate (DHA-S)]

The ripening effect of dehydroepiandrosterone sulfate (DHA-S) on the uterine cervix was studied after intravaginal application. A 100-mg suppository containing 0, 5, 10 or 20% (w/w) DHA-S was applied to the vagina of pregnant rats 3 times on days 14-16 of gestation. Wet weight and water content of the uterine cervix increased dose-dependently. To measure the elasticity of the uterine cervix, the tension causing an expansion of 1 mm or 2 mm was determined; this was reduced by the application of 20% DHA-S, and the difference in the length of the cervix produced by tensions of 5 g and 25 g was increased. Application of 20% DHA-S decreased the collagen content of the uterine cervix and the total collagenase activity was increased. Furthermore, histochemical changes, coarsening and edema were observed in the uterine cervix. These findings suggest that intravaginal application of DHA-S would produce ripening effects similar to those after intravenous injection.