It is true that constipation is easily caused during late pregnancy because after the fetus enters the pelvis, the rectum and bladder of pregnant women are directly pressed and the outlet is obstructed, so constipation easily occurs. In order to avoid this situation, in early pregnancy or before, pregnant women should establish good bowel habits. In the morning, there is more fluid in the intestines, which helps defecation, such as the habit of morning defecation, when the stool is softer, and because of the protection of intestinal fluid, the defecation will be smooth. Constipation is because the stool has reached the rectum, due to the poor defecation habits of pregnant women, the colon will re-absorb water, after a day and night the stool becomes dry, defecation will be difficult, coupled with the factors of the fetus in the body and the factors of the pregnant woman herself, there will be a vicious circle of defecation difficulties. Therefore, pregnant women must develop good bowel habits, and in the second trimester, pay attention to the intake of fiber in their diet, and consume adequate amounts of fruits, vegetables and water.