DHA supplementation for pregnant women try to start in the middle of pregnancy. DHA is an unsaturated fatty acid, pregnancy for maintaining fetal brain development has an important role, DHA human body can not synthesize their own, during pregnancy diet can supplement DHA, such as sesame seeds, peanuts, shellfish, marine fish, formula, etc., can rely on external supplementation, and in the stomach acid is broken down, with meals or food with food can be taken. Early pregnancy is still in the state of the gestational sac, the brain has not begun to develop significantly, at this time to supplement DHA does not have much significance, mid-pregnancy can be supplemented with DHA, at this time it is the peak of fetal brain cell development and proliferation, which is conducive to the development of the fetal nervous system. After pregnancy under the guidance of the doctor to supplement DHA, not to supplement too much.