Have you heard about sterile water injections, and want to know more?
Some women experience very painful lower back pain during labour, often due to the baby being in a posterior position.
A posterior position means the baby’s spine is against the mother’s spine, instead of baby’s back being outward, towards mama’s tummy.
This causes added pain, due to the pressure and weight on the mother’s spine (the baby is fine!).
Optimal fetal positioning is a great way to prevent a posterior baby.
But a posterior baby may be facing that way due to positioning of the placenta, the shape of the mother’s pelvis, and other reasons.
If you’re trying to avoid an epidural in labour, sterile water injections are an option.
What Are Sterile Water Injections?
Sterile water injections used for labouring women are injection of minute amounts of sterile water, into the skin.
The sterile water injections are a fairly new offering in the birth room, and have shown such wonderful results.
The injections aren’t available everywhere.
I wanted to find out more about how these sterile water injections worked, so I interviewed midwife Carolyn Hastie. Carolyn previously managed Belmont Birthing Service, and was NSW Midwife of the Year.
Q: Are Sterile Water Injections Really Just Water?
A: “Yes, it is really just water!”
Q: Who Came Up With The Idea To Do These Injections?
A: “From my understanding, the water injections being used for labouring women came from their use with people with renal colic/kidney stones. They are very effective for that condition.
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 it 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.
They’re 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) which 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 labour, 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.”
Q: When Should A Woman Use Sterile Water Injections For Back Pain?
A: “Some back pain is normal when the baby’s head is descending in the pelvis. It presses on the sacrum, pushing it out as the head turns on its way down.
That’s nature’s signal to the mother than the birth of her baby is imminent.
When a woman has intractable back pain, because of the baby being in the posterior position, then the water injections may be useful.”
Q: How Effective Are Sterile Water Injections?
A: “They are very effective for the majority of women.
The pain level of the back pain has to be a high enough level so that the wasp like sting is worth it.
On a 0-10 score, with 10 being the worst pain imaginable, the pain level has to be about an 8 or above.
I’ve seen lots of women have the injections, and only one has said it wasn’t worth it.
Her pain scale was not high enough when the midwives administered the injections.”
Q: How Quickly Does It Work and How Much Pain Does It Take Away?
“It works immediately and takes away the internal pain.”
Q: Do Sterile Water Injections Work For Everyone?
A: “Even the woman who said it wasn’t worth it pushed her baby out very quickly after the injections. Previously, she wasn’t pushing effectively before the injections, because of the pain in her back.”
Q: When Is The Best Time To Have Sterile Water Injections During Labour?
A: “They’re best used when the woman’s backache is 8 out of 10 and she can’t manage it.”
Q: What Advice Do You Have For Anyone Interested In Sterile Water Injections During Labour?
A: “Women could certainly ask their local service (hospital/midwives) about the use of these injections for back pain.
Janice deoCampo from Colac teaches how to do these injections, and has run workshops on using them.
She brought the idea to Australia, after her daughter used them in labour in Sweden.
Janice ran a workshop for us at Belmont Birthing Service and our midwives use them when necessary.
These injections are also being used at John Hunter Hospital. We wrote a policy and put the process through the Clinical Governance Unit for approval.”
Q: What Is Your Personal Opinion About Sterile Water Injections?
A: “These injections are fantastic. Quick, easy and safe. Women are able to stay mobile and there are no other effects from them.
Obviously, infection could be a risk, if sensible normal procedures were not followed.
We have actually used them for suprapubic pain (referred sensation from the cervix opening, felt just above the pubic bone).
This pain is another one of those indicators from nature telling the woman that labour is progressing, but for an occasional woman, she is not able to bear it.
We have found the sterile water injections work well there too – the system works all over the body because of the ‘gates’.
If the labour is a long one, the woman may need a couple of ‘doses’. But for many women, the relief of the internal pain enables her to relax, the pelvic muscles relax, the baby turns, the cervix dilates and out it comes! In second stage it can be amazingly fast.
In first stage it depends on how open the cervix already is when the injections are given as to how fast it goes.”
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 9&1/2 to zero in 2 contractions!” — Di
“I have used water injections for back pain in labour 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
a) Use fine needles 25 gauge
b) Use 0.1mL of sterile water (yes, that’s all)
c) Get the woman to point to where the pain is worst and inject there
d) Two midwives administer the water at the same time – the sting may stop the woman from having the other side done if only one midwife does it.
e) Have the partner hold the woman’s hands and talk her through the injections as she can automatically swipe at you when you give the injections
f) Administer the water injections into the skin, it’s intra-dermal, not sub cutaneous, not under the skin. The idea is to raise a little bleb which stretches the skin and sets off the receptors
g) Leave the area alone! the sting is the thing, if you rub it, it will lose its effectiveness.
h) The 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.