Abortifacient properties of an extract from Sida veronicaefolia.

A fraction from an alcoholic extract of Sida veronicaefolia, previously reported to be a potent oxytocic, was studied for its abortifacient effects in pregnant rats. Oral doses producing the abortifacient effects were greater than or equal to 32 ml/kg when administered from the 15th-17th day of pregnancy. Similar effects were produced by intravenous doses of greater than or equal to 3 ml/kg. At the minimum effective oral dose of 32 ml/kg, those animals that carried the conceptuses to term (40%) had litters with reduced average number/litter and weight. At twice this dose, only 10% delivered and the litters were sickly. The effects of intravenous administration of the extract was similar but more pronounced and included also some unique acute effects.