en پژوهشي Research Article In the present study, Plumbago zeylanica Linn. (Plumbaginaceae) , one of the folk medicinal plants commonly used as antifertility agent was evaluated for its antifertility effect. Five successive solvent extracts, petroleum ether, chloroform, acetone, ethanol and water extracts, of the stems of P. zeylanica were studied on estrous cycle at two dose levels, 200 and 400 mg/kg respectively. &nbsp; Of these, only the acetone extract was found to be most effective in interrupting the normal estrous cycle of the rats ( p <0.05) ( p <0.01) ( p <0.001 ). The rats exhibited prolonged diestrous stage of the estrous cycle with consequent temporary inhibition of ovulation. The antiovulatory activity was reversible on withdrawal of the extract. The effective acetone extract was further studied on estrogenic functionality in rats. The extract showed significant estrogenic and antiestrogenic activity ( p <0.05) ( p <0.01) ( p <0.001 ). Histological studies of the uteri were carried out to confirm the estrogenic activity. The results indicated the antifertility activity of Plumbago zeylanica stem extract in female Wistar rats. 169 0 http://ijpt.iums.ac.ir/browse.php?a_code=A-10-100-181&slc_lang=en&sid=1 sheeja Edwin 1003194753284600602 1003194753284600602 No Siddheshwar Balkrishna Joshi 1003194753284600603 1003194753284600603 No Dharam Chand Jain 1003194753284600604 1003194753284600604 No