Three days after the abortion surgery, coitus, easy to lead to infection, because a week after the abortion surgery, it is possible that the mouth of the uterus is not yet completely closed, this time coitus, especially in vivo ejaculation, it is very easy to bring the bacteria to the uterine cavity, and even retrograde infection to the pelvic cavity and lead to infection, which will affect the future pregnancy. If you have sex, it is best to use antibiotics empirically to prevent infection, such as oral antibiotics or intravenous antibiotics for 5-7 days, and you must go to the hospital for a follow-up ultrasound about half a month after the operation to see if there is any residue, and do a routine leukorrhea test to see if there is any vaginitis. In addition, to draw blood for routine blood tests to see if there is no elevation of blood, it is best to have sex more than a month after the abortion.