During labor, several different approaches are used in order to relieve pain, although not all these methods are supported by strong evidence. According to results of a study, examining previous reviews on the subject, there is more evidence that drug-based methods are effective at relieving labour pains than non-drug approaches. Results of the review are published in The Cochrane Library. The team examined the results of 15 previous Cochrane reviews and 3 non-Cochrane reviews, as well as data from 310 trials in total. The researchers split interventions into three categories, in order to analyze well- and less-supported pain relief methods.

The first category classified as "what works", included painkilling medications administered via epidural, combined spinal epidural (CSE), as well as inhalation. The methods in this category had more evidence that they were effective at relieving labor pains.

The second category classified as "may work", included relaxation, acupuncture, immersion in water, local anesthetic nerve blocks or non-opioid drugs, and massage. There was less evidence for these methods.

The third category, classified as "insufficient evidence", included aromatherapy, hypnosis, sterile water injection, biofeedback, injected or intravenous opioids, and transcutaneous electrical nerve stimulation (TENS).

The researchers found that although methods in the first category had the strongest evidence, more side effects were linked with the interventions, including hypotension due to epidural, and nausea and vomiting caused by inhaled painkillers.

In addition, they found that although interventions in the second category were less well-supported by clinical evidence, they were better tolerated, with women reporting improved satisfaction with pain relief for all apart from massage.

James Neilson of the Department of Women's and Children's Health at the University of Liverpool in Liverpool, UK, and lead author of the study, said:

"Women should be told about the benefits and adverse effects of different pain relief methods, but should feel free to choose whatever form of pain relief they feel would help them most during labour. It remains important to tailor approaches to women's individual needs and circumstances."

The researchers request that more studies are conducted on the non-drug interventions in the second and third categories. Even though these interventions were generally safe, for the majority, evidence was based on only 1 or 2 trials.

Less than 1,000 women participated in trials for each massage, aromatherapy, hypnosis, sterile water injection, and biofeedback. Even though TENS is popular and extensively recommended by midwives, it is not recommended by the National Institute for Health and Clinical Excellence.

Neilson, said:

"The discordance of views between women, clinicians and guidelines reflects a poor evidence base and the uncertainty should be resolved by a definitive clinical trial."

Written By Grace Rattue