Lettuce is rich in vitamin C, folic acid, carotene, dietary fiber and other nutrients, which can improve immunity, promote fetal development and prevent constipation during pregnancy. Moreover, lettuce is low in calories, which is beneficial to the control of weight and blood sugar during pregnancy. But it is not recommended for expectant mothers to eat raw lettuce. It is best to cook before eating to avoid bacterial pollution and pesticide residues. Chinese medicine believes that lettuce is cold, and people with spleen and stomach deficiency should eat it carefully. Expectant mothers are advised to eat according to their own physique.