DHA, named docosahexaenoic acid, is a kind of unsaturated fatty acid, which is an essential nutrient for human body, and it is generally recommended that pregnant women start to supplement it around 16 weeks of pregnancy. DHA is synthesized by alpha-linolenic acid in the body, and the amount of synthesis is very small, mainly obtained through food. DHA supplementation during pregnancy can promote the growth and development of the fetus, mainly promoting brain and sensory development. 1, promote brain development: DHA can participate in the development of brain cells and nerves, and in the formation of brain thinking and memory, supplementation of DHA can optimize the composition of phospholipids in fetal brain cells; 2, promote sensory development: DHA supplementation for pregnant women can promote the development of the fetal senses, including vision, hearing, and Tactile, can promote the fetal cerebral cortex sensory center neurons to grow more dendrites, can also promote the maturation of the fetal retinal photoreceptor cells. Therefore, during pregnancy, you need to consume the right amount of DHA, in addition to direct oral medication, you can choose dietary supplements, such as fish oil of deep-sea fish, high DHA content; flaxseed oil also has a high DHA content, which is a vegetable oil; in addition, many nuts also contain a certain amount of DHA, such as walnuts, peanuts, pine nuts, batanas, etc.. Pregnant women in addition to supplement DHA during pregnancy, we should also pay attention to strengthen nutrition, should consume sufficient vegetables, fruits, meat, eggs, milk, etc. to ensure the growth needs of the fetus.