How long to lie down after preparation for pregnancy and intercourse is not a precise time regulation, generally recommended to lie down for about half an hour, conducive to the semen flow into the body, increase the probability of conception. Women should not get up and move around immediately after intercourse when preparing for pregnancy, as gravity will make the semen flow out of the body. Lying flat for about half an hour is conducive to the semen passing through the cervix and flowing smoothly into the uterus, and there are more sperm and eggs to meet, and the chances of combining into a fertilized egg will increase, increasing the probability of conception. During the preparation period, you should accurately grasp the ovulation cycle, choose to have intercourse during the ovulation period, the chances of pregnancy will be greater. At this time, you should also maintain a healthy lifestyle, eat a balanced diet, be emotionally stable, do not have too much mental stress, and maintain a happy mood. Promptly carry out HCG measurement after sexual intercourse to observe whether the pregnancy is successful.