Objective: The objective of the present study was to evaluate the antifertility activity of ether (ErCD),chloroform (CeCD) and ethyl alcohol (EyCD) extracts of the whole plant of Cynodon dactylon in female Wistar albino rats.Methods: Acute oral toxicity and an antifertility study were performed in female Wistar rats with two dose levels (200 and 400 mg/kg,orally) of EyCD.The estrogenic and progestogenic effects of EyCD were further observed by administering it to immature Wistar rats by investigations of vaginal cornification,hormonal level,uterus weight,biochemical parameters,histopathology of the uterus and deciduoma formation,respectively.Isolation of EyCD was carried out by Flash Chromatography and isolated fraction was estimated by HPLC.Results: No toxicity with any of the extract was found up to the dose of 2000 mg/kg body weight.EyCD treated rats exhibited maximum reduction in pregnancy (83.33％).Estimation of EyCD on vaginal cornification,estrogen-induced uterotrophic assay and deciduoma model demonstrated vaginal cornification,significant (P ＜ 0.01) increase in uterine weight and uterine proliferation in histopathology and reduced deciduoma formation respectively.Hormonal and biochemical parameters confirmed the above findings indicating estrogenic potential and antiprogestogenic potential of EyCD that might be attributed to the presence of phytoestrogen (apigenin) in EyCD.Conclusion: The results suggested that extracts of C.dactylon possess significant antifertility activity,which is consistent with the literature reported in folk medicine of this plant in fertility regulation.