What form of pain relief is typically used that allows the mother to administer it herself?

Gas and Air, also known as Entonox or nitrous oxide, is a form of pain relief that allows the mother to control her level of pain management during labor. This combination of nitrous oxide and oxygen provides analgesia by providing a sense of relaxation and reducing the perception of pain.

The self-administering aspect is particularly significant as it empowers mothers to manage their pain according to their needs during contractions. By inhaling the gas through a mask or mouthpiece, they can adjust the dose and timing, which can enhance their feelings of control during the labor process.

The other options involve different methods of pain relief that do not typically allow for self-administration. Pethadine is an opioid painkiller given by injection, regional anesthesia (such as an epidural) is administered by healthcare professionals, and local anesthesia numbs a specific area but does not usually allow for self-administration in the same way. Thus, Gas and Air is distinctive in providing both self-control and effective pain relief.