The placenta has been formed in the 11th week of pregnancy, and the embryo is more stable at this time, so if the patient has no clinical discomfort, he can have intercourse. When coitus should pay attention to the following two aspects of the problem: First, the patient must pay attention to hygiene when coitus, it is best to carry out penis and vulva cleaning, because the patient is pregnant, the vaginal resistance is relatively low, do not pay attention to hygiene may lead to inflammatory diseases; Second, coitus should pay attention to the strength can not be too large, too large a force will make the patient’s uterus by the mechanical collision, pulling, resulting in the appearance of abdominal pain, bleeding and other symptoms of the first sign of miscarriage. The second is to be careful not to use too much force during intercourse, which will cause the patient’s uterus to be mechanically bumped and pulled, resulting in abdominal pain, bleeding and other signs of pre-miscarriage. If the patient is 11 weeks pregnant, there is abdominal pain, bleeding, or low placenta position, painless bleeding and other signs of preeclampsia, can not cohabit.