Whether or not a vaginal delivery is successful is generally not related to whether the placenta is attached to the anterior or posterior wall. The factors that determine the delivery are the force of labor, the birth canal, the fetus, and the mental and psychological factors. It is normal for the placenta to be attached to the anterior wall, posterior wall, lateral wall or fundus of the uterus. If the placenta is lower than the prenatal exposure, attached to the lower uterine segment, or the lower edge of the uterus reaches or covers the internal os of the cervix, i.e., placenta praevia, the mode of delivery will be affected. The factors that determine vaginal delivery are labor force, birth canal, fetus, mental and psychological. 1. Abnormal labor force: This includes all kinds of contractile force abnormalities (uterus, abdominal muscle and diaphragm, anorectal muscle). The main one is uterine contraction abnormality, which is categorized into weak contraction and strong contraction. Weak uterine contraction can lead to prolonged or stalled labor, while strong uterine contraction can cause rapid labor or serious complications. 2. Abnormalities of the birth canal: including abnormalities of the bony birth canal and abnormalities of the soft birth canal, with narrowing of the bony birth canal being the most common. Bony birth canal stenosis can lead to abnormal labor force or abnormal fetal position. 3. Fetal anomalies: including abnormal fetal position, relatively oversized fetus and abnormal fetal development. 4. Mental and psychological: although labor is a physiological process, it can produce psychological stress on the mother. Maternal psychosocial factors can cause a series of changes in the body, thereby affecting the force of labor, and is therefore one of the important factors in determining the delivery. Pregnant women are advised to undergo regular check-ups and to seek prompt medical attention if they feel unwell.