There are no clinical requirements for the correct posture for sleeping in the first trimester of pregnancy, and it is generally recommended that pregnant women sleep in a comfortable position. First trimester pregnant women should sleep in a comfortable position, because in the first trimester of pregnancy, the fetus is small, and generally will not be compressed or pulled. Pregnant women can sleep on their backs or on their sides, but they should be careful not to sleep on their backs for long periods of time. To the mid-late pregnancy abdomen began to show obvious bulging state, and the pressure of the fetus on the waist and abdomen of the pregnant woman also increased, this time it is generally recommended that pregnant women sleeping posture should be used side lying. The first three months of pregnancy should also pay attention to timely supplement folic acid, balanced diet, maintain a regular routine, avoid strenuous exercise.