The fourth week of pregnancy belongs to the early stage of pregnancy, in this period should pay attention to ensure that the intake of folic acid, iron, iodine, etc., and at the same time recommended to eat a light diet moderate flavor, avoid smoking and drinking. 1. Ensure folic acid intake: fetal neural tube development is mainly in the first four weeks of pregnancy, the mother’s folic acid deficiency may lead to fetal open neural tube malformation, etc., it is recommended to eat more liver, dark green vegetables and other folic acid-rich foods, and folic acid supplements can be taken under the guidance of a physician. 2. Ensure iron intake: during pregnancy, it is recommended to consume more animal blood, liver, lean meat, black fungus, red dates and other iron-rich foods. Iron deficiency or anemia can be under the guidance of the physician moderate intake of iron and vitamin C. 3. Ensure the intake of iodine, need to increase the intake of iodine during pregnancy, including the consumption of iodized salt, seafood and so on. 4. Nausea, vomiting and other symptoms may occur in early pregnancy, it is recommended that meals should be nutritious, less greasy, easy to digest and palatable, and try to consume more carbohydrate-rich cereals or fruits. 5. Avoid smoking and drinking alcohol, and recommend that pregnant women stay away from smoking environments.