Have you heard about sterile water injections, and want to know more?
The use of sterile water injections is a fantastic way to treat pain throughout labor.
It’s a quick and low intervention alternative to medical pain relief.
Sterile water injections work for general labor pain and are particularly effective for back pain during labour.
Sterile water injections can help you avoid an epidural. They can also provide relief while you’re waiting for an epidural.
What are sterile water injections?
Sterile water injections are very small (0.1ml) amounts of water, injected just beneath the outer layer of the skin. The injection really is just water!
Sterile water injections are a relatively new offering in hospital birth rooms, but many midwives around the world have been using these injections for over 50 years.
Working on certain nerve points is a method for reducing labor pain that’s been known to help for thousands of years. The idea of injecting water against these nerve points was only developed in the 20th century.
How do sterile water injections work?
Midwife Caroline Hastie from NSW explains:
“The concept behind the development of sterile water injections for pain is gate control theory.
Our skin has thousands of receptor sites and nerve cell endings. They scan for pain, pressure, touch etc, and can transmit that information to the brain very quickly.
Sensations shoot up the nerves and spinal cord to the brain. The sensations (which are chemical and electrical signals) go through little traffic control stations.
The signal boxes in the nerve pathways are ‘manned’ by chemical signalers which let pain, pressure, touch etc., signals through to the brain.
The signal boxes in the nerve pathways are called gates … because they choose which signal to let through. When the brain receives the signals, it decides what action to take.
The traffic controllers (chemicals) that man the gates preference skin signals over internal signals.
This is because the skin is monitoring the outside environment, and it lets the brain know when there is immediate danger.
When a woman has back pain in labor, the pain signals are slow, internally generated signals.
If a woman has the water injections into her skin, it stings for about thirty seconds. That sting switches on the fast fibres.
The fast fibre signals from the skin come racing up to the gate. The traffic controlling chemicals recognise an immediate threat, close the gate to the slow pain messages, and let the quick skin-related message through.
The internal pain signal is stopped in its tracks, and the woman no longer feels that internal sensation. That effect lasts for about 90 minutes”.
The nerve points where water is injected are known nerve receptors for back, uterine, cervical, and pelvic floor pain.
This means that most types of labor pain can be relieved in some way by sterile water injections.
Due to the way in which slow and fast-acting nerve fibres in the back work, sterile water injections are most effective for back pain during labor.”
Are sterile water injections for labor pain safe?
Yes! While hospitals have been slow to get on board with using sterile water injections in labor, recent research has shown that they are both safe and effective.
A recent study by the University of Queensland had more than a thousand birthing people, who were given either a placebo or sterile water injections. This study showed no risks or poor outcomes in either group.
Because sterile water injections don’t require any pharmaceutical medication and are injected just beneath the skin, the risks are very low.
The main risk is an infection of the skin around the site of injection. If standard aseptic techniques are used, this risk is also incredibly low.
Are sterile water injections for labor pain effective?
Again, yes! The same study by the University of Queensland found that twice the number of birthing people given sterile water injections reported significant pain relief when compared with the placebo group.
Most people find that their pain has to be significant for the sterile water injections to work most effectively. This means that they might be less effective in early labor, when pain is dull and less intense.
How quickly do sterile water injections work and how much pain do they take away?
They work quickly. And certainly more quickly than either opiates or an epidural.
In fact, sterile water injections work almost immediately. They cause a stinging sensation for about the first 30 seconds, and then it eases. Because the injection alters the communication between the nerve fibres and the brain, the pain continues to be eased for up to 90 minutes.
When rating the level of pain, out of 10, most people found their pain was reduced by at least 4 points. For example, if a person started with back pain rated 8/10, after the sterile injections this pain would be less than 4/10.
Do sterile water injections work for everyone?
No pain relief is 100% effective for 100% of people, 100% of the time.
Occasionally, even epidurals do not work during labor.
Research shows that sterile water injections work for 60-70% of people in labor. By comparison, opiates like morphine or pethidine are only 30-40% effective for reducing pain in labor.
When is the best time to have sterile water injections during labor?
The best time is when pain is significant and cannot be tolerated.
Due to the way in which gate theory works, sterile water injections might not be very helpful when pain is rated less than 7-8/10.
Are sterile water injections available in all birthing units?
No. Because the research into this form of pain relief is relatively new – even though the practice has been around for decades – it is not a standard offering in all maternity units.
It is more commonly offered in Europe and New Zealand; if you are in Australia or the US it will depend on your care provider.
If you’re interested in having sterile water injections during your labor, then ask!
The more birthing people who request this helpful treatment, the more the demand will be recognised, and the more widely sterile water injections will be available.
Are there other benefits to having sterile water injections in labor?
The research done by the University of Queensland showed a 3% reduction in the rate of caesarean section for people who had sterile water injections, compared with the placebo group.
Sterile water injections also reduce the need for an epidural. This treatment allows you to remain more active and upright during your birth. Staying active and upright is helpful for labor to progress more efficiently.
Comments about sterile water injections from other midwives
“I have only used this once, with rather miraculous results, so not really qualified to comment. Went from back pain scale 91/2 to zero in two contractions!” – Di
“I have used sterile water injections across many different births, and have only had one person who didn’t find it effective. That’s out of about 50 women I’ve used them for” – Yan
“I have used water injections for back pain in labor for the last 3 years in 2 different hospitals, always with amazing results. Very few women say it didn’t help at all” – Sally
Pointers for midwives or doctors interested in doing sterile water injections
- Use fine needles 25 gauge
- Use 0.1mL of sterile water (yes, that’s all)
- Ask the woman to point to where the pain is worst and inject there
- Have two midwives administer the water at the same time; the sting might stop the woman from having the other side done if only one midwife does it
- Ask the woman’s partner to hold her hands and talk her through the injections, as she might automatically swipe at you when you give the injections
- Administer the water injections into the skin; they are intradermal, not subcutaneous (under the skin). The idea is to raise a little bleb, which stretches the skin and sets off the receptors
- Leave the area alone! The sting is the thing. If you rub it, it will lose its effectiveness
- Swedish midwives give four injections – either as four in a row, across the back, or on the four points of an inverted trapezoid shape, on the woman’s sacrum.