Learning About Pudendal Nerve Block

A pudendal nerve block is an injection (shot) of medicine close to the pudendal nerve. It can numb the nerve and block pain. The pudendal nerve runs from the back of your pelvis to the muscles and skin in your anus and your vagina or penis.

There are three main reasons doctors might do a pudendal nerve block. It may be done to:

• Numb pain during an operation done to your vagina or anus, such as removing hemorrhoids. It might also be used to help with pain during vaginal childbirth. This is different from an epidural, which numbs the entire lower part of your body.
• Treat chronic painin your pelvic area that happens when the pudendal nerve is damaged, pinched, or irritated (pudendal neuralgia).
• Help find the source of pelvic pain. If your doctor isn't sure where your pain is coming from, they can do a pudendal nerve block to see if your pain goes away. This can help narrow down the best treatment option for you.

Before the procedure:

• Tell your doctor about any medicines or supplements you take.
• Let your doctor know if you might be pregnant.
• Follow any directions your doctor may give you for not eating or drinking before getting the nerve block.

You might get a sedative (a medicine to help you relax) through a needle into your arm. Usually, you won’t need general anesthesia (medicine to put you to sleep). You’ll lie on an exam table on your side, or on your back with your feet up in stirrups, depending on where your doctor will inject the numbing medicine.

There are three different ways to do a pudendal nerve block. Which one is right for you depends on why you’re getting it. It might also depend on whether you’re biologically male or female. The three options are:

• Transvaginal (through the vagina). If you’re getting the nerve block to help with pain during childbirth or to do an operation in your vaginal area, your doctor might choose this approach.
• Transperineal (through the perineum). The perineum is the area between your vagina (if you’re female) or scrotum (if you’re male) and your anus.
• Perirectal (next to the rectum). The rectum is the last part of your large intestine and connects to your anus.

To find the best spot to place the nerve block, your doctor will gently insert one or two fingers inside your vagina or rectum and feel for the ischial spine (a thin, pointy bone in your pelvis). They might also use imaging technology, like ultrasound or fluoroscopy (a type of X-ray), to help guide them.

After they identify the right spot, your doctor will inject a medicine to numb the skin in the area where you’ll get the nerve block. When the skin is numb, they’ll inject the medicine for the nerve block. Your doctor may do this on only one side or both sides.

Most people are able to go home the same day. If you had sedation to help you relax, you’ll need someone to drive you home from the hospital.

While you recover, avoid heavy lifting, strenuous exercise, and sitting for long periods of time. Your doctor can tell you when it’s safe to resume your normal activities.

The effects from the nerve block can last for days, weeks, or even years. It all depends on the type of medicine you got, the dose, and how well your body responds to the medicine. If you got a nerve block to treat chronic pain from pudendal neuralgia, you can repeat the procedure to control your pain in the long term. Some people repeat the nerve block once a month or as needed.

There is also a chance that the nerve block won’t work to relieve pain. If that happens, you’ll work with your doctor to try other things.

Like every operation, a pudendal nerve block has possible side effects and risks. The most common ones are:

• Soreness or pain where you got the injection.
• Numbness or weakness in the legs.

These usually go away within a few hours or days.

Serious complications are rare, but they can happen. These include:

• Infection or bleeding.
• Nerve damage.
• Organ damage to your bladder or rectum.
• Damage to the pudendal artery.
• An allergic reaction to the medicine.