If menstruation does not occur 1 month after the abortion, clinically, we must be alert to the possibility of uterine adhesion due to endometrial damage, and we recommend ultrasound to find out the thickness of the endometrium and to exclude the possibility of pregnancy. If the endometrium is obviously thin, it is highly suspected to be caused by uterine adhesion, you can take progesterone orally for 5 days, after stopping the medicine, usually 3-7 days after menstruation. If there is still no menstruation on the 8th day, and the thickness of the endometrium does not change on ultrasound, it is very likely to be the result of uterine adhesion. It is recommended to do a hysteroscopy to separate the adherent tissues and put an IUD in the uterus at the same time, so as to avoid reattachment of the adhesion.