Pregnancy sickness is usually most severe in the 9th to 10th week of pregnancy. The reaction of pregnancy vomiting varies from person to person, generally starting from 5 to 6 weeks of pregnancy, vomiting symptoms appear after breakfast or dinner, and it is most obvious in the 9th to 10th week of pregnancy, most pregnant women slowly disappear after the 3rd month of pregnancy, but there are some pregnant women who have nausea and vomiting will last for the whole period of pregnancy. Nausea and vomiting is a normal part of the early pregnancy reaction, and in early pregnancy, the fetus is relatively small and does not need a lot of nutrients, so parents do not have to worry that vomiting will affect the growth and development of the fetus. If the vomiting lasts for a long time and occurs frequently every day, it is necessary to go to the hospital and give symptomatic treatment to ensure the normal development of the fetus.