Everything Pregnancy

What Is an Epidural & How Does It Work?

Learn about spinal injections and epidural injections to decide if one of these forms of anesthesia is right for your labor and delivery. 

Epidural Dewald Kirsten/shutterstock

Every mom says it: No matter how many books you read or friends' stories you hear, you won't quite know how you'll feel during labor and delivery until you're actually in the midst of it. That said, you'll most definitely want to get a feel for your pain relief options ahead of time. The epidural is one of the most common forms of anesthesia. Here, the must-knows about the pain-blocking drug.

What is an epidural?

"Epidural anesthesia for labor pain relief is a type of anesthesia where pain medication is injected near the lower spine or backbone," explains Sangeeta Kumaraswami, M.D., an anesthesiologist specializing in obstetric anesthesia at Westchester Medical Center, the flagship of the Westchester Medical Center Health Network in Valhalla, New York. "It numbs the body below the injection, allowing a woman to remain awake and alert but more comfortable throughout labor, and feel pressure to push when it is time to deliver her baby. It can also be referred to as an epidural block or epidural injection." 

How does the epidural work?

When you're in labor, your uterus contracts, leading to pain that travels from the uterus via nerves in the spine or backbone to the brain, explains Dr. Kumaraswami. "The pain is usually mild early on in labor, but gets worse closer to delivery."

By opting to have an epidural, you can block those intensifying sensations. Iffath Hoskins, M.D., clinical associate professor in the Department of Obstetrics and Gynecology at NYU Langone Health in New York City, explains that the anesthetic agent is injected into the epidural space, which is a compartment surrounding the nerves in the spinal cord. "The anesthetic agent then bathes the nerves, which become numb and thus prevent the transmission of pain sensations," she notes.

What are the various delivery forms of the medication?  

  • Spinal injection: This form of the drug is a single injection that can be used alone or in combination with an epidural, explains Dr. Kumaraswami. "When used alone, it is administered through a needle inserted in the lower back into the spinal canal," she notes. "While pain relief is immediate, it will typically last from one and a half to three hours and could wear off before the baby is delivered."
  • Epidural injection: This form allows for additional placement of an epidural catheter (which is threaded into your epidural space, as the needle is removed, and the catheter is taped to your back). The catheter stays in place for the rest of the labor, Dr. Kumaraswami says. "Small doses of the medication can be injected at intervals, as needed," Dr. Hoskins says. "This relief can last for the duration of labor—up to 24-36 hours—plus several hours later. Epidural analgesia is also used in chronic pain situations which can last several days." It also bears noting that the actual location of the pain relief can be tailored with epidural versus it is more generalized with spinal. In some hospitals, you can get a "walking epidural" that won't limit you to your bed as much. That said, "You may not be allowed to walk once the epidural is in place due to safety and monitoring issues," notes Dr. Kumaraswami. 

If you happen to need a cesarean section or tubal ligation following the delivery of the baby, the epidural treatment can continue through these procedures. 

What are the potential side effects?

    Researchers have found that early epidural does not increase the rate of C-section delivery or affect the length of labor. As for the health of your baby, researchers say that an epidural does not affect the weight, APGAR score, or other measurements of the newborn.

    You may experience side effects such as decreased blood pressure, mild itching, back pain, and headache, notes Dr. Kumaraswami. "A major complication such as nerve damage, bleeding, and infection in the spine and paralysis are extremely rare events," she says. 

    To minimize risk, speak to your doctor beforehand about any medical issues, such as allergies to local anesthetics, breathing problems, bleeding problems, spinal surgery, etc., says Dr. Hoskins. You'll also do well to go slow when you start to move. "After delivery, wait to move until you've regained full feeling in the lower extremities because there is a high chance of falling and injury if there is residual numbness," she says.

    Ultimately, the pain of labor and delivery is different for every woman and for every pregnancy. Dr. Kumaraswami recommends women weigh their pain-relieving options by having discussions with the birthing educators, physicians, or midwives responsible for their care and then decide what method is best for them.