Objective:To evaluate the influence of low-dose aspirin on endometrial receptivity and pregnancy outcome of severe intrauterine adhesions after surgery. Methods:Totally 125 women with severe intrauterine adhesion treated by transcervical resection and Foley balloon were divided into 2 groups randomly:65 cases in group A were given progynova 3 mg

three times a day and aspirin 75 mg per day

while group B were treated with progynova only

both groups continued for one month. Endometrial thickness

type of endometrial

endometrial volume

the resistance index（RI）and pulsed index（PI）were observed. Hysteroscopy was performed after one and three months

and pregnancy outcome was followed up. Results:（1）Endometrium thickness was thicker in group A than in group B on the day of ovulation（P=0.000）and the proportion of type A endometrium was higher in group A than in group B

with significant differences（P=0.004）. Values of RI and PI were lower in group A than in group B

with significant differences（P=0.000）.（2）There was no significant difference in endometrial volume between the two groups（P=0.474）.（3）The effective rate in recovery of uterine cavity shape at 3 months postoperatively was 60.0%（39/65）in group A and 41.7%（25/60）in group B（P=0.040）.（4）All cases were followed up for 6-12 months;25 cases in group A had gestation

15 cases had pregnancy;21 cases in group B had gesration

6cases had pregnancy（P=0.033）. Conclusion:Low-dose aspirin can obviously improve the endometrial receptivity and pregnancy outcome of severe intrauterine adhesions after surgery.