It is forbidden to have intercourse during the third trimester of pregnancy; after the third trimester, the placenta has formed and intercourse is allowed if there is no sign of miscarriage in the middle of pregnancy; and it is not advisable to have intercourse in the last two months of pregnancy, which will increase the risk of premature birth and infection. For women who are just pregnant, often because the placenta is not fully formed and the embryo is not yet stable, if you have intercourse at this time, it may induce uterine contractions and increase the risk of miscarriage, so you can live and work normally during the first trimester, but avoid strenuous activities and prohibit intercourse. After the third trimester, as the placenta has formed and the fetal growth and development is more stable, intercourse can be arranged appropriately, but attention should be paid to the position during intercourse, which should not constitute excessive pressure on the abdomen, and the frequency of intercourse should not be too frequent. Once there is vaginal bleeding or contractions and other uncomfortable symptoms, intercourse should be stopped to avoid miscarriage. In the late stages of pregnancy, because the fetus is close to full term, the stimulation of intercourse can easily increase the risk of bacterial upstream infection and lead to premature rupture of the fetal membranes; the stimulation of prostaglandins in semen can also increase the risk of preterm delivery, so intercourse should also be prohibited in the last 2 months of pregnancy.