A vaginal breech birth is the birth of a baby from a breech presentation, in which the baby exits the pelvis with the buttocks or feet first as opposed to the normal head-first presentation. In breech presentation, fetal heart sounds are heard just above the umbilicus.
The bottom-down position presents some hazards to the baby during the process of birth, and the mode of delivery (vaginal versus Caesarean) is controversial in the fields of obstetrics and midwifery.
Though vaginal birth is possible for the breech baby, certain fetal and maternal factors influence the safety of vaginal breech birth. 
It is not always easy to determine the position of a baby in the womb, and you may be near the end of your pregnancy before it is possible to tell whether you have a breech baby. Your doctor will examine you manually to feel for the position of the baby’s head, and you will be given an ultrasound.
There are three main breech positions:
Frank breech: The buttocks are in place to come out first during delivery. The legs are straight up in front of the body, with the feet near the head. This is the most common type of breech position.
Complete breech: The buttocks are down near the birth canal. The knees are bent, and the feet are near the buttocks.
Footling breech: One leg or both legs are stretched out below the buttocks. The leg or legs are in place to come out first during delivery.