Sterile water injections during labour

Supporting information for women offered sterile water injections during labour.


You have been offered Sterile Water Injections as you may benefit from them during your labour.

If you experience severe back pain during labour Sterile Water Injections may help to reduce this back pain by up to 50 to 60%. This relief can occur from up to 10 minutes after they are given and lasts for 2 to 3 hours.


Two midwives give two small injections of sterile water into your lower back (four in total). These injections sting and so are usually given at the height of a contraction. The body’s response to

the Sterile Water Injections prevents pain signals from reaching the brain. No pain-relieving medication is given via these injections.


  • May reduce your back pain by up to 50 to 60% from 10 minutes to 2 to 3 hours
  • Can be repeated after two hours, up to three times during your labour
  • An effective option for pain management that is not pharmacological (no drugs) and does not affect either you or your baby
  • May avoid the need for further pain management (e.g. epidural) and/or intervention
  • You can choose to have additional analgesia at any point following administration of the injections (ie. Entonox, diamorphine and/or epidural analgesia)
  • Is safe for you and your baby


  • You will experience a painful stinging sensation during the injections which passes after 30 seconds
  • The injections may not work well for you
  • You will need to be positioned so that your midwives can access your lower back (sitting unsupported, all fours etc)