Abstract Asparagus africanus Lam., Asparagaceae, is used traditionally as medicinal plant for treatment of various gastrointestinal disorders and for birth related applications. This study aimed to evaluate anti-implantation potential, screening for bioactive phytochemicals and to determine its toxicity. Thirty healthy rats were distributed into five groups (n = 6). Pregnant rats were orally administered vehicle and aqueous extract A. africanus at three different doses thrice daily for seven days. Misoprostol 300 µg/kg bw was used as positive control. All rats were laparotomized 24 h after the last dose and number of live fetuses, implantations and resorption sites were enumerated, and ovaries were harvested for histopathology. The phytochemical analysis was carried out using LC/MS. Acute toxicity was investigated, the animals were randomly grouped into five groups (n = 3); control, four different doses of aqueous extract A. africanus at a single dose treatment and rats were observed for 14 days. Prenatal study demonstrated that 300 mg/kg bw of extract and misoprostol were significantly increased the percentage of anti-implantation as compared to untreated rats. Histopathology of ovaries showed a dose dependent toxicity. LC/MS revealed the presence of steroidal saponins; asparasaponin II, sarsasapogenin, spirostans, and stigmasterol. The mean weight gain of rats treated with 2000 mg/kg bw of aqueous extract was significantly reduced (p = 0.032) compared to control group. In conclusion, the aqueous extract A. africanus has anti-implantation effect in female rats and is safe up to 2000 mg/kg bw. In addition, it contains some potential steroidal saponins, which could be used to explain its anti-implantation activity, however this finding needs further pharmacological studies to confirm the antifertility activities.