There is no one answer to “what’s the best labor position”, however there are certain positions that allow your pelvis to open and your pelvic floor to lengthen better than others. Leaving room for your tailbone to move backwards vs it running into the bed (i.e. delivering on your back) and utilizing gravity as much as you can (think holding onto the back of the bed, a deep squat, hands and knees, etc.) are two really important things to think about when it’s time to push :)