Pain relief in labour

Giving birth is painful. It may be ‘positive’ pain and it may be short-lived, but it’s still pain, so it’s reassuring to know that there’s a range of pain relief options available.

What causes the pain?

No two women react the same way during labour and the degree of pain can vary widely. Labour pain is generally caused by the muscle contractions which push your baby out of the uterus, but it can also be caused by pressure from your baby, particularly if she is large for your pelvis or in an awkward position.

How it varies

‘The level of pain depends primarily on your pain threshold and the position of your baby’s head,’ says Janet Fyle, midwife policy advisor at the Royal College of Midwives. ‘For instance, a baby in the posterior position (with her spine against yours) is often associated with a longer and more painful labour.’

Labour pain also has a lot to do with how relaxed and comfortable you are. Being familiar with your surroundings - touring the labour ward beforehand, knowing the midwives and bringing in your favourite music may all help you relax.

Be informed

Keep an open mind about pain relief because women respond differently to different methods and it’s not always possible to predict your requirements.

‘The best preparation is to be well informed about your choices so you can actively participate in the decision-making,’ says Dr John Crowhurst, consultant anaesthetist at Queen Charlotte’s Hospital, London. ‘This'll help you feel in control, which itself can reduce the pain.’

PAIN RELIEF OPTIONS

Here we look at the range of different options available:

Relaxation techniques

 Pethidine
 Sedatives and tranquilliser
 Mobile epidural
 
TENS

 Fentanyl
 Epidural
 General anaesthetic
 
Entonox

 Meptid
 Spinal anaesthetic
 Alternative pain relief
 

Relaxation techniques: Mental and physical relaxation, a positive attitude, controlled breathing and massage can all help. ‘Women who practise yoga are mostly able to cope with the pain. They're more relaxed, which makes labour easier,’ says Janet Fyle.

TENS (Transcutaneous Electrical Nerve Stimulation): TENS uses a low-frequency current to stimulate the body’s production of natural pain-killing endorphins. Four electrodes are attached to your back and the intensity of the current is controlled by a hand-held push button, giving you complete control. It may need to be removed to monitor your baby and you are free to move around.

TENS has no effect on your baby or your mental alertness and studies show that it helps eight out of 10 women, normally reducing pain by 30-40%. However, you won’t be able to use a TENS machine if you have a pacemaker.

Entonox (nitrous oxide and oxygen): The most controllable and short-lived form of pain relief. It works by stopping nerve cells from communicating with each other - the pain's still there, but the brain’s perception of it is dulled. You may feel light-headed while inhaling it, but you'll regain full consciousness a few seconds later.

The gas is inhaled through a mouthpiece or face mask, and you control when you have it. Breathing in about 30 seconds before the peak of a contraction should give the gas time to dull the worst of the pain. It'll take practice to get the timing right, and may be worth trying early so you're prepared when you really need it. Entonox won’t affect your baby.

Pethidine: This opium-like (opioid) drug is given by injection and has quite a strong sedative effect, which is good if you are very tired as you'll feel relaxed and drowsy. But some women don't like the ‘out-of-control’ feeling they experience. The effects last about two hours and only one dose is recommended.

If given too close to delivery, pethidine can interfere with your ability to push. It can also depress your baby’s breathing and reduce her muscle tone, making her floppy. This is particularly worrying for pre-term or small babies, so pethidine shouldn't be used in these cases.

Fentanyl: This newer opioid pain killer must be given by an anaesthetist. The pain relief only lasts about 20 minutes, but it can be given repeatedly. It works in the same way as pethidine, so you may feel the same ‘out-of-control’ fuzziness. Fentanyl may be used if an epidural can’t be given, or if there isn’t time to set one up, for example, when the pain is very severe close to delivery.

Meptid (meptazinol): This drug is often seen as the home birth alternative to pethidine. It's a less potent form of pain relief, but may have less effect on your baby.

Sedatives and tranquillisers: These drugs are only used rarely, and only before labour is established. They can reduce anxiety and help you get to sleep if early labour is particularly long. They reduce alertness and have sedating effects on the baby, which can last for up to a week.

Epidural: This is a local anaesthetic injected through the lower back into the space between the spinal nerves and the backbone. It numbs the lower half of the body without interfering with your mental alertness. It takes 10 to 20 minutes for an anaesthetist to set up, and the effect is usually felt within a few minutes. A tiny tube is left in place so it can be topped up.

With an epidural, you may not feel the urge to push, so you may need an assisted delivery and continuous fetal monitoring may be necessary. Your legs may stay numb for several hours after delivery and loss of sensation in your bladder may mean you need a catheter to empty your bladder afterwards.

Once in place, an epidural can be used as the sole means of anaesthesia, should an assisted delivery or Caesarean section be necessary. Often an epidural is recommended if there’s a strong likelihood of a Caesarean because it means one could be done quickly without general anaesthetic.

Spinal anaesthetic: This is an injection of local anaesthetic directly into the spinal fluid. It works very quickly and lasts for about one hour. It’s normally used if an epidural is not in place, but a complicated assisted delivery is needed. It relaxe the pelvic region and can prevent tearing. It’s also becoming increasingly popular for Caesareans.

Mobile epidural: This technique uses a combination of a local anaesthetic and a pain killer. Because the drugs are injected directly into the spinal fluid, the dosage is smaller, which means you’re still able to stand and walk.

The mobile epidural has been pioneered at Queen Charlotte’s Hospital London since 1991 and is now used in about 25% of UK hospitals. It needs more frequent topping up than a conventional epidural, but you can be upright and make the most of the force of gravity to help with delivering your baby.

General anaesthetic: This is the most extreme form of pain relief and is usually only necessary if you need an emergency Caesarean. General anaesthesia will affect your baby who may need resuscitation.

Alternative pain relief: Techniques such as acupuncture and homeopathy are gradually becoming more accepted. Many hospitals will allow you to invite a practitioner into the labour room, provided they are given advance warning.

What the experts say

‘Severe pain can cause exhaustion, dehydration and distress. It can increase your heart rate, blood pressure and oxygen and glucose consumption, so there may be very good medical reasons for reducing or eliminating pain.’
Dr John Crowhurst, consultant anaesthetist at Queen Charlotte’s Hospital in London.