Calcium supplemented in late pregnancy will not be directly deposited in the head of the fetus, causing the fetus to be too hard, and proper calcium supplementation is helpful to the growth and development of fetal bones, and calcium deficiency may lead to various abnormalities in the mother and child. Generally speaking, as long as the development of the fetus is normal, its skull is hard, but because the skull is not composed of a single bone, there are gaps between the bones, and there are soft tissues covering the gaps, so it is soft to the touch, and calcium will not make the gaps between the bones disappear, and naturally will not make the skull hard. However, if there is a calcium deficiency, it may lead to muscle spasms, twitching of hands and feet of pregnant women, etc. It may also lead to poor bone development of the fetus and restricted growth of the fetus in the uterus. So calcium should be supplemented in moderation during pregnancy under the guidance of a doctor. Pregnant women should eat more food rich in protein during pregnancy, such as eggs, lean pork, soy products, milk and so on. It is also necessary to properly supplement shrimp, fish, pork liver, oats, walnuts, peanuts and other foods, eat more fresh vegetables and fruits, to ensure that the intake of food nutritionally balanced, to avoid a single nutrition.