The 2D ultrasound can see the face of the fetus, but the 2D is not as vivid and graphic as the 3D or 4D ultrasound. The ultrasound can see the face of the fetus regardless of 2D, 3D or 4D, and can be used for the detection of gross fetal structural malformations. Two-dimensional is plane imaging, three-dimensional, four-dimensional is based on two-dimensional imaging, such as three-dimensional is three-dimensional imaging, four-dimensional is based on three-dimensional plus the timeline, belongs to the dynamic three-dimensional. Generally, during the major screening examination, ultrasonographers will first use 2D ultrasound to screen the fetus for comprehensive malformations, and when it is found that the fetus may have abnormalities of the macroscopic structure, 3D or 4D probes will often be used to assist in the diagnosis. Therefore, the three-dimensional and four-dimensional imaging of fetal facial structure is more vivid than two-dimensional, but two-dimensional ultrasound can also see the face of the fetus. Pregnant women during pregnancy should pay attention to do a good job of prenatal checkups, actively listen to the advice of professional doctors to do a good job of comprehensive care and health care, pay attention to more rest, at the same time should be relaxed, to avoid nervousness, anxiety, there is any discomfort should be timely to the hospital, by the doctor to clarify the diagnosis and cooperate with the doctor to deal with the symptoms.