In the first trimester of pregnancy, which is the early stage of pregnancy, coitus is generally not recommended, and having sex in the early stage of pregnancy will have an impact on the pregnant woman and the baby. First, it is easy to cause preeclampsia, in this stage the uterus is particularly sensitive, if the number of sexual intercourse is too frequent and too strong, it is likely to cause preeclampsia, leading to abdominal pain and vaginal bleeding in pregnant women. Secondly, it is easy to cause infection, after pregnancy hormone levels change, the vaginal blood vessels have become more abundant, if you have sex at this time, and do not do a good job of personal hygiene, it is easy to lead to pregnant women infected with vaginal inflammation. So in the first trimester of pregnancy is not able to cohabitate, in addition to the late trimester of pregnancy can not cohabitate, if the mid-pregnancy resumption of sexual life should be moderate.