The 30th week of pregnancy belongs to the second trimester, at which time the baby’s head is usually in the position of the mother’s lower abdomen and the whole thing is upside down. Because of the sufficient amount of amniotic fluid in the uterine cavity before 28 weeks, the fetus has a large range of space to move, so the head of the fetus may be in any position in the mother’s stomach, and can change at any time. However, as the fetus gradually increases in size after the 28th week of pregnancy, the space for the fetus to move around in the uterus is limited, and from then on, the baby’s head should normally be in the mother’s lower abdomen, or else it will be considered an abnormal fetal position. Once the abnormal fetal position is detected, pregnant women should not be too nervous, because even if the abnormal fetal position can be restored to the normal fetal position, even if it can not be restored to the normal fetal position, cesarean section can still be chosen to treat. It is recommended to have regular checkups during pregnancy and closely observe the baby’s development.