The main medical pain-relieving options for labour include nitrous oxide (laughing gas), injections for pain (such as pethidine or morphine) and epidural anaesthesia
The main medicines for pain relief during labour include nitrous oxide (laughing gas), opioid medicines and epidural pain relief.
Nitrous oxide (also called laughing gas or Entonox)
- Nitrous oxide is a gas you breathe in through a mouth piece when you're having a contraction.
- The gas takes a few seconds to work, so it's best to breathe from the mouth piece as soon as a contraction starts.
- Nitrous oxide doesn’t stop the pain completely but can lessen the pain of each contraction for some people.
Possible side effects
- Nausea (feeling sick), vomiting (being sick), confusion and disorientation.
Opioid medicines
- Common examples of opioid medicines include fentanyl, morphine, remifentanil and pethidine.
- These medicines are given through a drip (IV line) in your arm or hand, or an injection in your muscle.
- They don't block the pain completely but help to ease it.
- In some parts of Aotearoa New Zealand you might be given a pump to give yourself these medicines in labour called called patient controlled anaesthesia (PCA). You can ask your midwife or LMC what is available where you are having your baby.
Possible side effects
- Opioids can cause nausea, make you feel sleepy (sedated), and slow your breathing. Because of this, you will be monitored carefully after you’ve had these medicines.
- Opioids can also slow breathing for your baby after they are born or make them sleepy; this is more common with pethidine than other opioids. For this reason, pethidine is not used if you are in later stages of labour. Your baby will be closely checked after birth and their breathing will be supported if it’s slow.
Epidural pain relief
- Epidural injections are one of the most effective medicine-based pain relief option for child birth.
- They are placed in your lower back (at the level of the top of your hip bones) between the bones of your spine.
- A needle is used to put in a small plastic tube (called an epidural catheter).
- Local anaesthetic (a numbing medicine) and an opioid medicine are given through the epidural catheter.
- This takes away the pain of labour, while leaving you with some of the feelings of labour (eg, tightness with contractions) and you can still move your legs and push when it’s time to have your baby.
- Around 1 in 10 people still have some pain after the epidural medicine is given. Let your LMC know if you still have pain so they can adjust the epidural.
- After you’ve had an epidural your baby’s heart rate will be monitored closely. Your blood pressure will also be checked regularly.
- An epidural can cause your blood pressure to drop, this can make you feel faint or unwell and can affect your baby’s heart rate. If this happens, you will be given some fluids through your drip and medicine to improve your blood pressure if needed.
- An epidural can cause some muscle weakness in your legs and make it hard to move around. A lower dose epidural can make it easier to move around the room. Ask your LMC if this is available in your area.
- When you have epidural pain relief you might not be able to tell when you need to urinate (pee/mimi). Some people may also need a urinary catheter (a tube in to your bladder) so you can pee/mimi.
- An epidural does not:
- increase the chance of needing a Caesarean birth.
- increase the chance of needing forceps or ventouse birth to help the baby come out.
Possible side effects of an epidural
- Shivering/shaking or fever.
- Itchiness.
- Headache – around 1 in one hundred people. If this happens, you may need another epidural or other medicines to relieve it.
- Pain or tenderness where the epidural was placed.
- Very rare side effects include infection, bleeding, nerve damage.
- Talk to your LMC about the risks and benefits of all of the pain relief options so you can choose what is best for you.
Video: Epidural Pain Relief in Labour- NZ Society of Anaesthetists and WDHB
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(NZ Society of Anaesthetists and Waitematā District Health Board, NZ, 2016)