A human embryo at eight weeks of pregnancy is called an embryo and cannot be called a fetus. At this point the embryo takes shape and is about sixteen millimeters long. In the eighth week of pregnancy, the embryo begins to take on a human form, the organs differentiate and develop, and the heart is formed. The head is the larger of the two, taking up nearly half of the entire body, and can be distinguished from the ears, nose, eyes, mouth, fingers, and toes. . At this time, pregnant women may experience early pregnancy reactions such as chills, dizziness, fatigue, drowsiness, anorexia, aversion to oil and grease, preference for sour flavors, nausea and vomiting. For pregnant women who have not had prenatal checkups, they should have their first prenatal checkup, develop a pregnancy health care handbook, determine the week of pregnancy and predict the expected date of delivery, assess the high-risk factors during pregnancy, and provide education and guidance on pregnancy health care and pregnancy-related knowledge.