Abortion as a remedy for unwanted pregnancy is widely used in China, especially in the last 10 years the development of painless abortion, so that people ignore the hazards of abortion while alleviating the pain of abortion surgery, many women have significantly reduced menstruation after abortion surgery, and some even amenorrhea. Clinically diagnosed as: A-S syndrome, through the analysis of a large number of cases, the main causes of reduced menstruation are: 1. The endocervical lining or endometrium is damaged during abortion scraping and adhesions occur after surgery. If the cervical canal is adhered, it is difficult to discharge menstrual blood. These patients often have monthly cyclic abdominal pain, low menstrual volume and dark color. If the uterine adhesions are large in extent, they can cause amenorrhea, and small in extent, they can reduce menstruation. 2, excessive scraping of the uterus or multiple abortions, especially with short intervals, resulting in multiple successive damage to the endometrium, which cannot be repaired, and the entire endometrium of the uterus is seen to be defective or white scarred under the hysteroscope, losing the menstruation formed by periodic endometrial exfoliation. 3, a few because of incomplete scraping of the uterus with tissue residue and resulting in amenorrhea or reduced menstruation, need to be scraped again to remove the uterus can restore normal menstruation. But at the same time, it is inevitable to cause secondary damage. In addition, the reason for low menstrual volume after abortion is: excessive mental tension and anxiety, as well as premature intercourse and tub bath after surgery, resulting in post-abortion infection. Some women have endocrine changes after abortion, which can also cause low menstrual flow or amenorrhea. Therefore, abortion (including medical abortion) is traumatic and can cause a series of problems such as low menstrual flow or even amenorrhea after abortion, thus affecting life, so do not use abortion as a means of contraception, if you do not want to have children for the time being, you must take a reliable contraceptive method, so as not to cause future sterility due to abortion. After the abortion, you need to pay attention to rest and strengthen nutrition. Do not engage in heavy physical labor and strenuous activities within half a month, avoid contact with cold water, keep the vulva clean and hygienic, prohibit intercourse within a month, and do not take a tub bath within half a month to avoid bacterial attack and infection. Once the above situation occurs, after the doctor’s diagnosis, you need to seize the time to treat it correctly. In the past, the solution was: to dilate the uterus and cervix with a cervical dilatation rod, which is simple and easy to do, but the disadvantage is that there is a certain blindness, and it is impossible to understand the degree of damage and defect of the endometrium, especially for severe adhesions which cannot be implemented at all. Therefore it is rarely used nowadays.