Not taking calcium tablets during pregnancy may have an effect on the development of the fetus. The growth and development of the fetus during pregnancy requires adequate nutrition. Generally, after the fourth month of pregnancy, the development of the fetus’s bones and brain requires a large amount of calcium. Food supplementation cannot satisfy the needs of the pregnant woman and the fetus, so the pregnant woman needs to take extra calcium supplements to meet the needs of the fetus’ growth. If a pregnant woman does not take enough calcium supplements, it will not only affect the development of the fetus, but also have an impact on the pregnant woman, who may experience symptoms such as leg cramps, lumbar pain and other symptoms, and in severe cases, it will also affect her daily life. Therefore, pregnant women should not only pay attention to strengthen the nutrition, eat more calcium-rich food, in the fourth month of pregnancy to follow the doctor’s advice for additional calcium supplements, usually also pay attention to sun exposure, to promote the absorption of calcium.