In most cases, the fetus has a large head and short legs, which should be considered to be caused by calcium deficiency. It is necessary to go to the hospital to have the calcium level in the blood checked. You need to take calcium supplements, including oral solution of calcium and zinc gluconate, or even intravenous injection of calcium gluconate. At the same time, pregnant women should get more sunshine, eat more calcium-rich foods such as milk, soy products, seafood and so on. Appropriate sports exercise, in the calcium supplement, but also supplement some vitamin D, preferably in the night calcium supplement.