As a midwife experienced in assisting some 4000 births, most of them vertically, I am very enthusiastic about squatting whether before or after labor has started. However, there can be a hitch. First of all we need to differentiate between squatting with the heels being pulled up and squatting with the foot soles making full contact with the floor. The latter position means squatting more deeply. This allows the abdominal contents to come down and gives rise to greater pressure being exerted onto the uterus from the thorax for instance. When the baby's head is not yet engaged in the pelvic inlet, the membranes may rupture prematurely and consequently a prolapsed cord can develop. Again I am talking from experience. Therefore, I do not recommend deep squatting during the last two months of pregnancy if the head is not engaged. During labor deep squatting means opening the pelvic outlet. If the baby's head is still high in the birth canal, no form of squatting is appropriate at that moment. Opening of the pelvic outlet goes at the expense of the measurements of the pelvic inlet. The pelvis is involved in a scissor-like movement depending on the hip joints being either stretched like in a standing position or flexed as during squatting. If the presenting part is above the pelvic floor, meaning that the pelvic inlet is still involved, fetal distress can be brought on by squatting.

However, when at the start of the second stage the woman takes a standing position, labor continues in a wonderfully relaxed manner. She need not push actively, because the baby's weight takes the child down. So she does not get tired. Once the baby's head touches the pelvic floor, the woman feels the need to push, and nobody can stop her from bearing down and ending in a squatting position. And when the baby's forehead is born, most women lean backward, thus allowing the pelvic inlet to widen to allow the shoulders to pass. I call this the ballet of the second stage.

— Gre Keijzer, midwife
The Netherlands