Approximately 30% of women will have this sort of constant low back pain during labor. As a result of the baby's position, the nerve roots at T11 and T12 level are irritated . These are the same nerves that supply the back and therefore the pain is seems to be coming from that area.

Interestingly, this is usually a very difficult problem to treat with the usual methods of labor pain control. Sterile water papules offer a medication free, easily performed method that is very effective for this specific kind of pain. The technique works up to 93% of the time and the relief can last as long as 90 minutes. It can be repeated if necessary.

The injections are easy to perform. The procedure involves four separate injections of small amounts of sterile water just below the skin on the lower back using a small needle. The injection itself is initially painful (like a bee sting) but can be done during a contraction so that it is less noticeable. The technique works best in the first stage of labor and seems to work more reliably when done early.

This technique technically can be done by the obstetrician, a family practitioner, even an experienced nurse. If used as a sole technique, it does not need the presence of an anesthesiologist since no medication is being given and there are almost no risks to the procedure when done properly.