The timing of labor is mainly related to the ripeness of the cervix, the function of the placenta, and the hormone levels in the body, and there is generally no special relationship between low fetal head and early labor. 1. Cervical ripeness: it is mainly about the softness, hardness, length and opening of the cervix. A low fetal head may promote the ripening of the cervix, but it will not lead to early labor. 2. Function of the placenta: if the placenta is mature and does not have aging, fibrosis and other conditions that affect fetal growth, it can provide the baby with the nutrients it needs for growth and development as well as oxygen, so it will not give birth early; however, if the placenta functions abnormally, it may lead to lack of oxygen for the fetus, and it may be necessary to give birth early. 3. Hormone levels: If the levels of estrogen and progesterone and human hairline gonadotropin are abnormal, it may indicate that the placenta is abnormal and may require early delivery. Generally, the obstetrician will assess the pelvis, cervix and other indicators of the mother in the late pregnancy to prevent preterm labor.