Abstract： Objective To explore the impact of uterine artery embolization (UAE) with embosphere on endometrial microvessel density (MVD). Methods Sixty-nine healthy female guinea pigs were randomized into control group (n=12), UAE group (n=45) and sham operation group (n=12). The UAE group was further divided into A1, A2 and A3 subgroups (n=15 each). UAE group underwent bilateral uterine artery embolization with embosphere (trisacryl gelatin microspheres) and eventually, there was 1 death each in A1 and A2 subgroups, such that either subgroup A1 or A2 consisted of 14 animals which were apparently normal. The sham operation group underwent normal saline injection through uterine artery. No procedures were given to the control group. Uterine specimens were obtained during ovulation period:between post-UAE days 7 and 15 from subgroup A1, days 16 and 30 from subgroup A2, days 31 and 45 from subgroup A3, and days 16 and 30 from the sham operation group and control group. The microvessels over the endometrial basal layer were detected by immunohistochemistry, and the MVD was calculated in each group for statistical analysis. Results The MVD in subgroups A1 and A2 was both significantly lower as compared with the control group and sham operation group [(9.64 ± 2.48)/field, (14.36 ± 2.73)/field vs (18.44±3.20)/field, (17.63±2.71)/field, all P＜0.05]. The MVD in subgroup A2 was significantly higher than that in subgroup A1 (P＜0.05), but lower than that in subgroup A3 (17.15±2.87)/field (P＜0.05). The MVD in control group did not differ from that in the sham operation group or A3 subgroup. Conclusions The MVD of endometrial basal layer reduces during a certain period of time after UAE, which may have some negative effect on endometrial receptivity. However, the endometrial MVD may gradually resume normal over embolization time.