Nitrous oxide is a new option for labor pain relief. What is it, how does it work, and is it right for you?

Pregnant Woman In Labor Holding Laughing Gas Nitrous Oxide Mask
Credit: Tyler Olson/Shutterstock

Nitrous oxide, also known as "laughing gas," has been used for decades as a labor pain-relief option all over the world. In the UK, it's estimated that 50-75% of people use "gas and air" during birth—you might have seen women breathing it in and out on the popular show PBS show Call The Midwife. But for American mothers, nitrous oxide in labor is still a bit unusual. Here's everything you need to know about nitrous oxide during childbirth.

What is nitrous oxide and how does it work?

Yes, nitrous oxide is similar to the gas you might get at the dentist. But as Michelle Collins, CNM, Ph.D., a certified nurse midwife at Vanderbilt University Medical Center and expert on the use of nitrous oxide in labor in the United States, explains, it's not the same concentration—and doesn't have quite the same giggly effect.

In the United States, nitrous oxide for use during labor is administered at a 50/50 concentration of nitrous and oxygen, versus the 70/30 in dental offices. Most often, it's given to people through an FDA-approved device called Nitronox, which is a small machine on wheels (with tubing and mask attached). The laboring person places the mask on their face and begins breathing before the onset of a contraction, then breathes the gas through the contraction. Collins says, "Women find their own rhythm. Some breathe the whole time, other use it every other contraction or so, and others take breaks throughout."

Nitrous has a number of benefits for people in labor, including a fast effect, low cost, and the opportunity to remain mobile and change positions (something that can help labor progress). Nitrous can be used anytime during labor. For Laura Goetzl, M.D., MPH, the physician director of maternal-fetal medicine and medical director for labor and delivery at Temple University Hospital, one of the largest benefits of nitrous oxide is that it's patient-controlled: "The person controls when they want to use it, how often, and when they want to stop. Plus, the half-life is about five minutes, so it's out of your body very quickly."

Risks of nitrous use are relatively low. It's not recommended for people who have vitamin B12 deficiency, recent surgeries where gas could collect in the body (like gastric bypass) or people who cannot hold the mask to their face. It does not have any effects on babies, either while still in utero or once born. Side effects of NO2 can include nausea, dizziness, and drowsiness.

What does nitrous oxide during childbirth feel like?

Nitrous has a different effect than epidurals or IV narcotics. Dr. Goetzl explains: "It works by relaxing people. A lot of pain is heightened by fear, as we associate pain with bad things happening to us. Nitrous can help lessen the fear." Nitrous makes users feel calm. They will often still feel pain, but may feel somewhat removed from it. Women using nitrous still have the option to choose other pain medication.

Hillary Catlin, CRNA, a Washington D.C.-area nurse anesthetist and mother of a two-year-old son, was attracted to nitrous for its non-invasive qualities. Although she's administered hundreds of epidurals in her career in anesthesia, she was hoping to avoid one so she could remain active and upright in labor.

Nitrous oxide is not effective as an epidural at controlling pain—the goal of an epidural is to provide pain relief that is as complete as possible via medication, while nitrous is an "anxiolytic," meant to control anxiety. Many people who use nitrous go on to have an epidural as their labor progresses, according to the American Society of Anesthesiologists.

Still, a 2017 study in Anesthesia & Analgesia found that women who used nitrous in labor were just as satisfied with their pain control as women who used an epidural. For Collins, nitrous oxide is "another menu option," available so women can make informed decisions about their births, based on their histories, goals, and preferences.

Dr. Goetzl says satisfaction in labor is often dependent on your expectations: "If you're wanting an unmedicated birth and you use this, it can be great. But if you're expecting to feel no pain during labor, it might not be a good option." For those wanting to birth without interventions or pain medication, nitrous is often helpful to "take the edge off," allowing mobility and use of other comfort measures like massage, a TENS unit (which blocks pain receptors in the skin), or the use of showers and baths. It is also beneficial for people who cannot use an epidural due to medical issues, like low platelet count.

But if you're someone who knows you definitely do want an epidural, nitrous can still help—it's a useful option during early labor or while waiting for the epidural itself. Collins has seen nitrous aid in relaxation during epidural placement and with breakthrough pain once an epidural is in effect, too.

Nitrous worked well for Catlin, helping her achieve her goal of avoiding an epidural. Her labor was 19 hours overall, and she requested nitrous at around hour 13, using it during and after her son's birth: "It really helped me calm down. I remember starting to feel a little out of control and the nitrous eased the panic and anxiety. I was very relaxed for the next hours. I still knew what was going on, but it wasn't bothering me."

Aside from active labor, nitrous has other uses in the birthing room. Collins explains nitrous can aid discomfort during other procedures, like the insertion of a Foley bulb for induction, during the repair of the perineum after birth, or even for an external version to try to turn a breech baby. It's also great for fast labors, when women arrive at their birthplace very close to giving birth—during these situations, using nitrous during pushing can provide some relief if it's too late to get other types of analgesia.

What do I do if I want to use nitrous oxide?

Ask your doctor or midwife if your birthing facility offers nitrous. If so, ask questions about if you'd be a good candidate, how and when it's administered (in some hospitals, nitrous is given by the anesthesia team, but in most, it's controlled by nursing staff) and if there are any hospital policies you should understand before you're in labor. Although nitrous is becoming more common in the U.S. (Collins estimates more than 300 hospitals and about 70 birth centers currently offer it, up from just two hospitals in 2011), it's essentially inaccessible if your facility doesn't already offer it. If it's not available at your facility and you're interested in nitrous, let your provider and hospital administration know. Consumer interest, says Collins, can be powerful.