Epidurals and spinals are two types of regional anesthesia for labor and delivery.
When the uterus contracts, pain impulses travel from the uterus to the brain via nerves in the spine. Epidural anesthesia and spinal anesthesia involve placing local anesthetics within the backbone to block these pain impulses.
With epidural anesthesia, the local anesthetic medication is injected outside of the sac containing the spinal fluid and spinal cord. The nerves are blocked in this epidural space.
With spinal anesthesia, the needle pierces the sac containing spinal fluid and spinal cord, and the local anesthetic medication is injected into the spinal fluid. The nerves are blocked in the spinal space. The spinal needle is introduced into the spinal space below the level of the spinal cord so that the spinal cord is not injured.