The study examined the effect of DS147,the bioactive component of the traditional herbal recipe Bangdeyun,on pregnancy in mice with embryo implantation dysfunction induced by controlled ovarian stimulation (COS),and the underlying mechanisms.Female mice were superovulated by intraperitoneal injection of 7.5 IU of pregnant mare serum gonadotropin (PMSG) followed by an additional injection of 7.5 IU hCG 48 h later to establish embryo implantation dysfunction (EID) model.Pregnant mice were randomly divided into normal control group,COS group and DS147-treated groups.The pregnancy rate and the average implantation site were obtained on pregnancy day 8 (PD8).The side effect of 200 mg/kg of DS147 on naturally pregnant mice was also observed.Further,the uterine and ovarian tissue samples were collected on PD5 for measuring their weights,observing the development of the endometrium and ovary,and detecting the endometrial expression of MMP-2,TIMP-2,CD34 and angiogenin (ANG).The female mice treated with DS147 at doses of 100 to 800 mg/kg showed a higher pregnancy rate than those in COS group,and the highest pregnancy rate of 83.3% occurred in the 200 mg/kg DS147-treated group.Moreover,no obvious side effect was found in mice treated with 200 mg/kg DS147 on PD8 and PD16.The ovarian and uterine weights,and the expression levels of MMP-2,ANG and CD34 were significantly increased in DS147-treated groups when compared with COS group.The TIMP-2 expression level was much lower in DS147-treated mice than in COS mice and the ratio of MMP-2/TIMP-2 was much higher in DS147-treated group than in COS group,and even higher than normal control group.In all,these findings suggest that DS147 may improve pregnancy in mice with COS-induced EID by promoting matrix degradation and angiogenesis,and improving the development of corpus luteum and endometrial decidualization around the implantation window. The study examined the effect of DS147, the bioactive component of the traditional herbal recipe Bangdeyun, on pregnancy in mice with embryo implantation dysfunction induced by controlled ovarian stimulation (COS), and the underlying mechanisms. Male mice were superovulated by intraperitoneal injection of 7.5 IU of pregnant mare serum gonadotropin (PMSG) followed by an additional injection of 7.5 IU hCG 48 h later to establish embryo implantation dysfunction (EID) model. Pregnant mice were randomly divided into normal control group, COS group and DS147-treated groups. pregnancy rate and the average implantation site were obtained on pregnancy day 8 (PD8). The side effect of 200 mg / kg of DS147 on naturally pregnant mice was also observed. Future, the uterine and ovarian tissue samples were collected on PD5 for measuring their weights , observing the development of the endometrium and ovary, and detecting the endometrial expression of MMP-2, TIMP-2, CD34 and angiogenin (ANG). The female mice trea ted with DS147 at doses of 100 to 800 mg / kg showed a higher pregnancy rate than those in COS group, and the highest pregnancy rate of 83.3% occurred in the 200 mg / kg DS147-treated group. Moreover, no obvious side effect was found in mice treated with 200 mg / kg DS147 on PD8 and PD16. The ovarian and uterine weights, and the expression levels of MMP-2, ANG and CD34 were significantly increased in DS147-treated groups when compared with COS group. The TIMP- 2 expression level was much lower in DS147-treated mice than in COS mice and the ratio of MMP-2 / TIMP-2 was much higher in DS147-treated group than in COS group, and even higher than normal control group. these findings suggest that DS147 may improve pregnancy in mice with COS-induced EID by promoting matrix degradation and angiogenesis, and improving the development of corpus luteum and endometrial decidualization around the implantation window.