A new pregnancy can be aborted, but not until a gestational sac appears before a surgical or medication abortion can be performed. If the gestational sac is not observed by ultrasound, a medical or surgical abortion may fail at this time, resulting in an incomplete or invalid abortion. After the woman has intercourse, the fertilized egg will be formed, and the fertilized egg will be laid in about 1 week, HCG in the blood will rise rapidly and the gestational sac will start to develop, and the gestational sac will be found under ultrasound about 6 weeks after the last menstruation. When the diameter of the gestational sac is 1-2 cm, a medication abortion can be taken, but as the gestational sac increases, the medication abortion may be incomplete and a manual surgical abortion should generally be chosen, which can more thoroughly remove the residual embryonic tissue in the uterine cavity. It is important to note that whether a woman chooses a medication abortion or a surgical abortion, she should be alert to the problem of post-operative infection after the abortion. Once the infection occurs, the endometrial repair will be slowed down and the infection can also lead to pelvic inflammatory disease and endometritis, which can lead to lifelong infertility in serious cases. In addition, women should avoid sexual intercourse for 1 month after abortion, clean their vulva with warm water frequently, change their underwear regularly and pay attention to vaginal bleeding at all times.