In general, the baby will be born around 40 weeks of pregnancy, 40 weeks 280 days belongs to the due date, the due date is only an approximate date, 2 weeks earlier or 2 weeks later than the due date, the baby is born belong to is a normal performance. The fertilized egg may be formed early or late, and the development of the fetus in the abdominal cavity may also vary. The time of birth is also different due to the different nutrients consumed by the pregnant woman during pregnancy and the development of the fetus. If the birth is before 38 weeks or 42 weeks, it is normal. After reaching the due date, you should pay attention to ultrasound to check the development of the fetus, the condition of the placenta and the specifics of the amniotic fluid in the uterine cavity.