Antiimplantation and pregnancy interruption efficacy of Rivea hypocrateriformis in the rat

Petroleum ether, chloroform, ethanol and distilled water extracts of the aerial parts of the plant Rivea hypocrateriformis (Convolvulaceae) were tested for antiimplantation and pregnancy interruption properties in female albino rats. Among these, the ethanol extract was found to be most effective in causing significant antiimplantation and interruption of early pregnancy. The antifertility activity of ethanol extract was reversible on exogenous administration of hydroxy progesterone. However, the same ethanol extract was found to be ineffective in interruption of late pregnancy. Among the four extracts subjected to preliminary phytochemical screening, the active ethanol extract showed positive tests for alkaloids, glycosides, saponins, tannins and phenolic compounds.