Antiovulatory and Anti-Implantation Potential of the Methanolic Extract of Seeds of Abrus Precatorius in the Rat

Abstract

To investigate the effect of the methanolic extract of seeds of Abrus precatorius on the estrous cycle, ovulation, and implantation of fetuses in Sprague-Dawley rats. Cyclic female rats were randomly classified into 4 groups (A through D). Treated rats in group A had daily vaginal smears for a total of 64 consecutive days while being fed A precatorius extract for the first 32 of those days. Treated rats in group B received a single oral dose of the extract on the day of proestrus and were killed the following morning so that shed ova could be counted. Treated rats in group C received A precatorius extract from postcoital day 1 to 10 and were killed on day 12 to assess for anti-implantation effect, whereas the treated dams in group D received the extract from the 6th to the 19th day of gestation. The control animals in all 4 groups received an equal volume of distilled water. The methanolic extract of A precatorius caused a reversible disruption in the estrous cycle of the regularly cyclic rats and completely blocked ovulation in all the treated rats. Despite successful mating of the female rats with male rats of proven fertility, uterine dissection on postcoital day 12 revealed neither implantation nor resorption sites in all the animals treated with A precatorius. The extract of A precatorius caused a decrease in mean body weight, mean crown-rump length, and mean tail length of fetuses of the treated rats. There is a need to continue the search for new antifertility agents that have minimal side effects and widespread acceptability in addition to being reversible, affordable, and accessible. In this study, methanolic extract of A precatorius seeds caused reversible alterations in the estrous cycle pattern and completely blocked ovulation in Sprague-Dawley rats. In addition, the extract demonstrated anti-implantation activity and the potential to affect gross fetal morphometry in rats.