The baby can hear outside sounds in the stomach, the fetus has hearing after four months, and the hearing of the fetus above six months is basically close to that of an ordinary person. When the fetus after four months, can be carried out fetal education, the sound of music can stimulate the fetal auditory organs, promote brain development. When there are changes in the sound of the surrounding environment, it will cause fetal movement. When the surrounding noise is particularly loud, the fetus will feel uncomfortable, and when the environment is quiet, the fetus will become quieter. Therefore, pregnant mothers try not to go to the place where the noise is particularly loud during pregnancy, to avoid the fetus from becoming irritable and causing an increase in fetal movement, and a quiet environment can make the fetus more comfortable, which is conducive to the establishment of a good rhythm of activity. To sum up, the baby in the stomach is able to hear the outside sound, which is also the reason why the fetal education begins in the fetal period.