Women should not have sex in the first two months of pregnancy, because the embryo is not very stable in the first trimester, and the stimulation of intercourse during this period may easily cause pre-eclampsia, especially for women who have a history of spontaneous abortion, they should never have sex in the second trimester of pregnancy. In general, women should not have sex in the first and second trimesters of pregnancy, because in the first trimester, the embryo is not firmly established, and the stimulation of intercourse can easily cause preterm miscarriage, and in the second trimester of pregnancy, the uterus gradually increases in size, and the woman’s movement is gradually inconvenient, so it is not suitable to have sex. In addition, in the second trimester, the stimulation of intercourse can easily cause premature rupture of the fetal membranes, causing infection, and stimulation can also easily start contractions resulting in preterm labor, so women should choose the appropriate time for sex according to the situation to avoid adverse consequences.