Pregnant women can drink pure milk, because pure milk is rich in calcium, and the calcium content per 100ml milk is as high as 120mg, and the absorption rate of calcium in milk can reach more than 40%, which is helpful for pregnant women and fetuses to supplement calcium. Yogurt is rich in lactic acid bacteria, which can promote gastrointestinal peristalsis, effectively relieve constipation during pregnancy and increase appetite. Yogurt is made of fresh milk fermented by lactic acid bacteria, which has the same nutritional value as fresh milk, and has the functions of inhibiting the propagation of spoilage bacteria and reducing the production of toxins in intestinal tract. Moreover, yogurt can decompose lactose and protein in milk, making it easier for human body to digest and absorb. Pure milk and sour milk have their own advantages. For pregnant women who do not have severe pregnancy reaction, it is best to drink them alternately. Especially in the second and third trimester of pregnancy, the daily calcium intake of pregnant women has increased. In order to get enough calcium and vitamin D, it is best to drink milk and yogurt alternately.