This cohort study was conducted to investigate whether aspirin could promote the endometrial growth and repair, reduce the recurrence of intrauterine adhesion and improve the menstruation and reproductive prognosis after surgery for severe intrauterine adhesion. Menstruation was evaluated for the first time with a method similar to visual analogue scale (VAS) in which the menstruation was assessed by the patients themselves with 0 as amenorrhea and 100 as normal menstruation. This evaluation avoids the vague terms (such as large or small menstrual blood volume) in previous evaluations and considers the individual difference in menstrual blood volume and different understanding about the menstrual blood volume. Thus, this evaluation is easy to master, quantify and analyze.