If the usual menstruation is relatively regular, usually in about 40 days after menopause can do abortion, but before abortion first of all should be tested coagulation analysis, blood cell analysis, electrocardiogram and gynecological ultrasound, these test results are not abnormal, and rule out contraindications to abortion, you can abortion. Generally, when you do ultrasound for abortion, the ultrasound shows that the size of the gestational sac is about 1.2cm before it is allowed, otherwise it is easy to cause leakage of suction, and it is easy to have an incomplete abortion. If the month is too small, the gestational sac and blood clots mixed together, not easy to identify. If the month is too big, it is easy to bleed a lot during the abortion. Therefore, in general, if the menstrual period is regular, do ultrasound on the 40th day of menopause, and the ultrasound shows that the size of the gestational sac is about 1.2-1.5cm to do abortion is more suitable.