Does anyone know what is a good pain reliever during birth other than epidural?

I would like to recommend Obstetric TENS, model no. SD-600OB. The obstetric TENS is a compact design for easy use in a hospital to relieve pain during women's natural delivery. It works by sending soothing pulses across the surface of the skin and along the nerve fibers. The pulses prevent pain signals reaching the brain, just like a gate not letting anything p. They also stimulate your body to produce higher levels of its own natural painkillers.