The fetus in the fourth month of pregnancy has already developed all organs, has a human shape, and has a small amount of hair, the weight is usually around 110~120 grams, the length is around 16~17cm. The fourth month of pregnancy belongs to the mid-pregnancy stage, at this time the fetus can basically be seen in the shape of a human being, and the limbs can move flexibly, the fetus’s ears, nose, and mouth, eyes, and other organs have begun to develop, some pregnant women at this time can feel the fetal movement. In the fourth month of pregnancy, the fetus is about 110-120 grams, the top hip length is about 12-13 cm, and the length of the body is about 16-17 cm. the fetus grows faster at this time, so the pregnant woman needs to supplement enough nutrition, and eat more food with high content of protein and calcium, such as milk, eggs, and seafood, lean meat, etc. The pregnant woman should also pay attention to regular visits to the hospital to deliver the baby. Pregnant women should also pay attention to regular hospital checkups to understand the development of the fetus, and should pay attention to any abnormal symptoms, timely medical examination and treatment.