Entering the second trimester, the growth rate of the fetus accelerates, especially the rapid growth of bones, and the blood volume of pregnant women also increases greatly. Once the diet is unbalanced, it is easy to become deficient in calcium and iron. Calcium and iron supplementation are important tasks during pregnancy. How to supplement? Today we will discuss this issue. Calcium supplementation After 20 weeks of pregnancy, fetal bone growth accelerates, and bones begin to calcify at 28 weeks of pregnancy. The fetus alone needs to deposit about 110mg of calcium every day, which comes entirely from the mother\’s body. From this point of view, every pregnant woman needs calcium supplements. Calcium supplementation should start with diet.