Calcium supplementation for pregnant women is not the earlier the better, nor is it the more the better. Under normal circumstances, pregnant women should eat more calcium-rich foods and do not need to take extra calcium preparations such as calcium tablets in large quantities, as the calcium absorbed by food is sufficient to meet the needs of the pregnant woman and the fetus. However, if a pregnant woman has been experiencing poor appetite and loss of appetite during pregnancy, it is necessary to add additional calcium products for calcium supplementation. 1, calcium supplementation without adequate vitamin D, calcium can not be absorbed by the body. However, if you are not careful and take too much vitamin D, it can cause poisoning in the body. Many pregnant women take multivitamins, which depends on the total amount of calcium taken, while our Chinese diet and physique and other circumstances, or to supplement the amount of vitamin A. Because of the misguided doctors and manufacturers, now supplemental vitamin A and vitamin D appear many differences. 2, pregnant women must pay attention to the dosage of calcium supplements. Taking a large amount of calcium at one time will close the receptors, resulting in calcium not being absorbed. Therefore, each dose of calcium should not be too large. Pregnant women can divide 600-800 mg of calcium into 2-3 doses. Try not to take more than 500 mg at a time. 3, the clinical findings of many pregnant women taking calcium tablets will appear constipation, I personally think that pregnant women, especially in late pregnancy can be supplemented with probiotics, lactobacillus calcium powder or better, not only to prevent constipation, calcium powder to be easier to absorb than calcium tablets, conditioning pregnancy gastrointestinal discomfort, hardness, ease, will not cause the placenta, cranial bone aging. If a pregnant woman takes too much calcium tablets, it will not only easily lead to premature closure of the fetal cranial suture, but also easily lead to obstructed labor, and in serious cases, even premature aging of the placenta, thus causing abnormal fetal development. In addition, the huge uterus of women during pregnancy compresses the pelvic vessels and ureter, and if combined with high urinary calcium, it will increase the chance of dangerous urinary stones, and high calcium intake is not conducive to the intake of other trace elements into the body.