During labor and delivery, pregnant women may choose to receive pain relief called epidural analgesia, which is the delivery of a numbing agent through the back and into a body space around the spinal column. This numbs the area of the stomach and the pelvis. Typically the numbing agent is lidocaine, which is a local anesthetic like your dentist uses. Some times the numbing agent is combined with another medication that causes drowsiness and relieves pain called a narcotic. One of the risks associated with having this kind of pain relief is unintentional puncture of a sheath of tissue that surrounds and protects the spinal cord when inserting the needle. This sheath is called the dura. This would cause the fluid surrounding the spinal cord to leak out and this would cause a headache. This headache is called a post-dural puncture headache [PDPH]. The headache can be mild or severe. Rarely, PDPH can be serious and cause bleeding or small clots in the brain and damage to nerves that come out of the brain.