Objectives: To evaluate the effect of medical interventions on the sonographic appearance of endometrium in the infertile women with endometrial abnormalities and the clinical outcome of controlled ovarian stimulation cycles.Methods: Transvaginal ultrasonography was performed in follicular phase in natural period.30 of 60 infertile patients found with abnormal endometrial echoes were treated with hysteroscopy assisted dilation curettage(HADC group),another 30 with dilation curettage(DC group).The controls were 50 infertile women without identifiable endometrial abnormalities.The controlled ovarian hyperstimulation cycles were performed after treatment.Results: In HADC group and in DC group,the rate of type A endometrial echoes was significantly increased in controlled ovarian hyperstimulation cycles than in nature cycles,and the rate of type B,type C echoes was significantly decreased(P0.05).But compared with that in control group,the rate of type A endometrial echoes was significantly lower in HADC group and in DC group,and the rate of type B,type C echoes was significantly higher(P0.05).The clinic pregnancy rate in HADC group(56.7%) was statistically higher than that in DC group(43.3%) and in control group(40.0%)(P0.05).There was no significance difference between DC group and control group(P0.05). Conclusion: It is suggested that dilation curettage,especially hysteroscopy assisted dilation curettage,may be benefit to improve intrauterine disorder and increase clinic pregnancy rate.