You should not have intercourse in the first and second trimesters of pregnancy. Because the fetus is not stable in the first trimester, if you have intercourse, it may cause miscarriage and vaginal bleeding. The last two months of pregnancy should not have sex either, because intercourse may cause premature rupture of fetal membranes, and early rupture of membranes may lead to upstream infection of vaginal pathogenic microorganisms, causing uterine cavity infection, puerperal infection, etc., or stimulate induced contractions, causing premature birth, miscarriage, and premature babies may have low viability, abnormal development or even cerebral palsy. If you touch the placenta attachment site during sex, it can also cause placental abruption. After the pregnancy, you can have sex in the middle of the pregnancy, but pay attention to the action must be gentle during intercourse, and be careful not to press the abdomen in the position.