I think you might have meant stretching the cervix. The lady partsl wall expands on its own. The nurse caring for a laboring woman can use her fingers to stretch and gently manipulate the cervix back over the presenting part, usually the baby's head, toward crowning. It may prevent cervical tear. Analgesia is not necessary, and this is a common practice in most of the world, where analgesia in labor and delivery is almost non-existant.