Soon after the cervix is completely dilated, the mother will feel a strong urge to push. Pushing moves the baby through the birth canal, under the pubic bone, and out the vaginal opening. The past 20 years have seen differences in medical opinion regarding if a woman should start pushing immediately after she has reached 100% dilation, regardless of whether the urge has begun.
Some researchers theorize that this approach is harmful to both mother and child. However, a 2018 clinical trial showed women who pushed immediately upon full dilation delivered about half an hour faster than those who waited to do so.