Soymilk is rich in amino acids, protein and some trace elements, such as iron, copper and other minerals. Moderate consumption of soy milk in late pregnancy can not only supplement their own protein needs, but also promote fetal brain development. Soymilk also contains a lot of isoflavones, which can stimulate pregnant women to produce more amniotic fluid, which has the effect of making up for the small amount of amniotic fluid in late pregnancy. Soymilk also has the effect of laxative, in the late stages of pregnancy will be constipated phenomenon, because the head of the fetus descends into the pelvis, it will lead to bowel movement, causing constipation. During pregnancy should be balanced nutrition, reasonable arrangement of meals, especially in late pregnancy, should eat more fresh fruits and vegetables, can promote defecation.