The method involves the injection of a tiny dose of sterile water under the skin where the pain is. This is a relatively unusual way of alleviating pain in child birth. Women who wish to avoid pain-relieving drugs often choose acupuncture. For the first time, the effects of these two methods have been studied scientifically.
The study covered 128 birthing women at the delivery ward at the Kärn Hospital in Skövde, Sweden. At the start of labor the women were asked to indicate how much pain they were experiencing on a scale between no pain at all and the worst imaginable pain. In the same way, the women were asked to say how tense they were. Half of the women had their pain alleviated with acupuncture, while the other half received injections of sterile water. The women were then asked several times during labor how much pain they were experiencing and how tense they were.
“Injections of sterile water proved to be significantly better when it comes to alleviating pain, but the method was also better in terms of the women’s degree of relaxation,” says Lena Mårtensson, a midwife.
It has not been scientifically elucidated just how sterile water relieves pain, but one theory is that the injection triggers the body’s own pain-inhibiting system. The researchers believe that the most sensitive nerve cells are stimulated and send a more rapid signal to the brain. This results in other pain impulses not reaching the brain.
Injections of sterile water were more common in the early 1990s, but many women experienced pain from the injection itself.
“Now we have devised a way to administer the injections that doesn’t hurt as much. When we jab a bit deeper and administer a somewhat larger dose, we can achieve the same positive effect without the shot hurting,” says Lena Mårtensson.
Today acupuncture has taken over as the most popular alternative method for relieving labor pain. A questionnaire among Swedish midwives indicates in the dissertation that 25% of women giving birth are now treated with acupuncture, whereas only 2% are given shots of sterile water.
“Like many other midwives, I have been able to see that injections of sterile water are extremely effective for labor pains. Now that we have refined the injection technique, I hope more women will dare to request the method again,” says Lena Mårtensson.
The dissertation is for the degree of doctor of medicine at the Sahlgrenska Academy, Department of Clinical Sciences, Section for Obstetrics and Gynecology.
Title of dissertation: Sterile Water Injections and Acupuncture as Treatment for Labour Pain
The dissertation will be publicly defended on Friday, September 29, at 1:00 p.m., in the auditorium of the Women’s Clinic, SU/East, Göteborg