Pregnant women have various nutritional deficiencies as their nutritional needs increase with each week of pregnancy, and calcium deficiency is a common problem. Vitamin D is to promote calcium absorption, hydroxy vitamin D both 25-hydroxy vitamin D, the composition is the presence of vitamin D form, test hydroxy vitamin D is currently recognized as the best way to evaluate vitamin D nutrition, test results are divided into severe deficiency, deficiency, deficiency. The low hydroxy vitamin D belongs to the test result is insufficient, indicating that the body of pregnant women need to supplement vitamin D. Supplemental vitamin D ways are: 1, sun exposure, in a suitable temperature environment at 8-9 a.m., 4-5 p.m., direct sunlight state outdoor activities in the morning and afternoon for 30 minutes each. 2, food supplementation, such as more diets containing vitamin D. 3, drugs or health supplements, you can take drugs Vitamin D or health products vitamin D. Preventing calcium deficiency in pregnant women is also a measure to prevent fetal and neonatal calcium deficiency, pay attention to nutrition during pregnancy to maintain good health, keep sleep, eat more green vegetables and high protein diet