Pregnant women are generally advised not to have sex during the first and second trimesters of pregnancy. Since the placenta is not yet particularly fully formed in the first trimester, sex may cause uterine contractions that may lead to miscarriage, so sex during this period is generally not recommended. Since the uterus will gradually become more sensitive under the effect of hormone levels in the second trimester, sex may lead to uterine contractions, which may cause placental abruption or cause the possibility of preterm labor, so it is also generally not recommended to have sex during this period. So pregnant women who want to have sex consider the time in the middle of pregnancy after the third month of pregnancy, at this time the placenta has been formed, and the connection with the mother is more solid, the probability of miscarriage is significantly lower, but should pay attention to grasp the scale of sexual life, the number of times of sexual life should not be too much. If sex during pregnancy is uncomfortable, you should consult a doctor in time to give targeted treatment.