Calcium tablets for pregnant women are usually taken after the 4th month of pregnancy, as the calcium requirement of pregnant women increases greatly at this time. Generally women need to take calcium tablets after 4 months of pregnancy because the fetus grows and develops faster, and the pregnant woman’s demand for various nutrients will increase greatly. If a pregnant woman is deficient in calcium, it may lead to the emergence of lower limb convulsions, which will affect the quality of sleep, and may also affect the growth and development of the fetus. After the fourth month of pregnancy, pregnant women should pay attention to eat more calcium-containing food, such as milk, eggs, meat, fish and shrimp, etc., and also need to take calcium tablets under the guidance of the doctor, such as calcium dihydrogen phosphate, calcium gluconate and so on. In order to promote the absorption and utilization of calcium, appropriate supplementation of vitamin D, and pay attention to more sunshine. During pregnancy, a woman’s diet should be diversified, avoiding partiality and picky eating, which is conducive to the supplementation of all kinds of nutrients, and is conducive to the growth and development of the fetus. During pregnancy, pay attention to more rest, at the same time should relax, avoid tension, anxiety, any discomfort should be timely to the hospital, by the doctor to clarify the diagnosis, and cooperate with the doctor to deal with the symptoms.