At 17 weeks of pregnancy, most pregnant women already see a bulging abdomen in their appearance. At 4 months of gestation, the uterus has reached the bottom of the uterus about 3 fingers below the belly button. At 17 weeks of gestation, the fetus has a biparietal diameter of about 4 cm and weighs about 150-200 g. The fetal organs have already developed and taken shape. After entering the middle of pregnancy, the fetal development will accelerate and the demand for nutrition will increase, so pregnant women should pay attention to increasing nutrition, such as multivitamins and minerals, and pay attention to a balanced diet, not only to control the weight not to gain excessively, but also to pay attention to a diversified diet.