Three-dimensional ultrasound is mainly used to check the development of the fetus, the placenta, umbilical cord, amniotic fluid for abnormalities, uterine adnexa and so on. 1. Fetal development: 3D ultrasound can provide a clearer understanding of the growth and development of the fetus in the mother’s body. Usually in the 24th to 32nd week of pregnancy to do three-dimensional ultrasound, in this stage of the fetus, the body organs are developing, length and weight changes, through the three-dimensional ultrasound can be more clearly observed in various parts of the fetus changes. 2. Placenta: through the three-dimensional ultrasound can observe the shape and position of the placenta with or without anomalies, if found to have malformation of the placenta, placenta previa, placenta previa and other problems, can be detected in time and take measures to avoid serious consequences. 3. Umbilical cord: Observe the changes of the umbilical cord through 3D ultrasound, if there are problems such as umbilical cord around the neck, it can be detected and corrected in time. 4. Amniotic fluid: The amount of amniotic fluid can be roughly calculated through 3D color ultrasound to determine whether there is excessive amniotic fluid or too little amniotic fluid. 5. Uterine adnexa condition: The mother’s uterine adnexa, such as ovaries and round ligaments of the uterus, can also be observed through 3D color ultrasound. It is recommended that pregnant women who find abnormalities in their 3D ultrasound should consult their doctors in time to improve the relevant examinations and standardize the treatment.