Pregnant women can take DHA throughout their pregnancy, but it is most appropriate to take it in the middle and late stages. DHA is a kind of polyunsaturated fatty acid, known as “brain gold”, is an essential nutrient for brain nutrition, at the same time, DHA can promote the maturation of retinal photoreceptor cells, which is very important for the development of fetal brain, vision and hearing. Under normal circumstances, starting from the 5th month of pregnancy, the neurons in the fetal brain divide and mature the fastest, and there is a great demand for DHA. Therefore, it is crucial to supplement DHA in the middle and late stages of pregnancy. However, the intake of DHA is not the more the better, too much supplementation will cause nutritional excess, it is recommended that pregnant women can be supplemented according to the doctor’s instructions in moderation.