A pudendal block is a type of local anesthesia used for women who are giving birth. This medication is injected into the area of the pelvis that houses the pudendal nerve, which controls sensations to a woman's external genitals. Pudendal blocks are often given when a woman is in the second stage of labor to relieve pain that is affecting the perineum, which is the area between a woman‘s anus and genitals. It also relieves pain in the vulva, which is the outer, visible part of the genitals, as well as pain and pressure inside the vagina.
A regional form of anesthesia, a pudendal block is usually administered to relieve pain, pressure, and burning sensations in the vaginal and rectal area as the baby’s head emerges from the vaginal canal. Some types of anesthesia are used to provide relief from the pain caused by labor contractions, but a pudendal block works differently. It is not effective for treating the pain of labor contractions, so it isn't usually administered in early labor. Instead, it is administered right before a woman’s baby will emerge from her body. This anesthesia may not only help to relieve the pressure caused by the baby’s emerging head, but may also prevent pain if a woman must receive an episiotomy, which is a cut to the perineum that makes the vaginal opening larger.
Two medications that are commonly used for pudendal blocks are lidocaine and chloroprocaine, though there may be others appropriate for this use as well. In many cases, doctors prefer to use lidocaine since its effects last longer than chloroprocaine's. Chloroprocaine can provide effective pain relief, but doesn’t usually last for a full hour.
While pudendal blocks are generally thought to be safe, there are some concerns a woman may have about their use. For instance, the use of this type of block may sometimes make a woman’s urge to push her baby out less intense. Some women may be allergic to the medication used for a pudendal block and suffer symptoms of an allergic reaction as a result of its use. It is also possible for the drugs used for this type of anesthesia to cross the placenta and reach the baby; in some cases, this may cause the baby to breastfeed poorly at first. Additionally, some women may be concerned because a pudendal block may require the use of a large amount of anesthesia.