The 4D ultrasound shows hydrocephalus in the fetus, which needs to be observed for two weeks and then reviewed. It also needs to be combined with prenatal screening or prenatal diagnosis of the fetus, and MRI (magnetic resonance imaging) of the brain to detect or rule out whether the fetus has combined chromosomal or other malformations. The degree of hydrocephalus and the presence of other malformations should be taken into account. If the hydrocephalus is simple and mild, it can be absorbed on its own. If it is severe or combined with other malformations, the prognosis is poor and prenatal counseling is needed to make an informed choice whether to terminate the pregnancy. If hydrocephalus is found in the child on 4D ultrasound, if the fetus has hydrocephalus on both 4D ultrasound examinations and the amount of hydrocephalus is high, due to its complex etiology, most of the fetuses need surgery after birth, but it cannot be cured and the intelligence may be seriously affected, so most of the pregnancies are terminated to achieve the goal of eugenics.