Women can not have intercourse in 12 weeks of pregnancy, the main reasons are as follows: 1, 12 weeks of pregnancy belongs to the early stage of pregnancy, at this time the fetal development is still unstable, intercourse is likely to cause miscarriage, especially for pregnant women with symptoms of pre-eclampsia, intercourse will greatly increase the risk of miscarriage; 2, the development of the placenta in early pregnancy is not mature, the uterine wall and the placenta is not closely connected, intercourse is likely to cause bleeding, affecting the 3, pregnant women in early pregnancy body progesterone secretion is not enough, and there will be more pregnancy reaction, resulting in pregnant women’s body fatigue, coitus at this time will increase the fatigue of pregnant women, affecting the normal development and growth of the fetus. Pregnant women can have sex in the middle of pregnancy, but pay attention to the frequency and strength, it is recommended not to exceed 3 times a week, if the symptoms of discomfort to stop in time.