Research about Epidurals

Epidural analgesia involves an injection of local anaesthetic into the lower region of the spine. This numbs the nerves which transmit the pain of labour.

The drugs and methods used vary between hospitals. Either a regional anaesthetic such as bupivicaine, or an opiate such as fentanyl may be given, or a combination of the two.¹⁷ The drug may be administered in a single dose, as a continuous infusion, or by a pump controlled by the woman.

The effective control of pain during labour by the use of epidurals is well-established, although a small proportion of women find the pain relief ineffective.⁴⁸ Most women who use epidurals would use one again in a subsequent pregnancy.

Of more concern are the number of possible side effects of epidural anaesthesia.⁴⁹ Some of these affect the normal progress of labour:

• Where epidurals are used, there can be an increase in the length of both first stage and second stage of labour.
• There is an increase in the use of syntocinon to speed up labour.
• There is an increase in malposition of the baby, possibly caused by a failure to rotate.
• There is an increase of the number of instrumental deliveries (although this is not the case if the epidural is allowed to wear off for second stage).
• Epidurals can cause "epidural fever", a rise in maternal temperature which can lead to changes in the fetal heart rate and may also result in the mother and baby being treated with antibiotics.

Other side effects which may affect women's experience of labour⁵⁰ include:

• a loss of mobility, resulting in women being confined to bed, and difficulties pushing during the second stage of labour
• the need to be catheterised to allow the woman to pass urine
• itching caused by opiates in the drugs used for epidurals
• nausea and dizziness caused by a drop in blood pressure

Other side effects can persist after the epidural has worn off:⁵⁰

• A dural tap headache affects about 8 in 1000 women, and can be severe in about 6 of those women. These can last for 10 days or longer, although it may be possible for it to be treated.
• There is a possibility that epidurals can cause long term backache, although research has not shown a link.
• There can be serious complications associated with the use of epidurals but these are extremely rare.

There is some evidence to suggest that the drugs used in epidurals can affect the baby after birth, although further studies need to be done.⁵⁰

More recently there has been a trend towards reducing the dose of local anaesthetic and adding an opiate to reduce the loss of mobility and feeling caused by epidurals. Whilst maternal satisfaction has improved, there appears to be no reduction in the operative delivery rate compared with conventional epidurals.⁵¹

For women who wish to avoid an epidural, the following can help:

• using self-help techniques for pain relief, such as water, massage, aromatherapy, distraction techniques, TENS machine¹⁷
• staying upright and mobile throughout labour¹⁷
• already knowing the midwife who is with you during labour⁸
• having the continuous support of a female experienced in childbirth⁹
• giving birth at home⁶ or in a community unit such as a midwifery-led unit²⁷
• having your baby's heart beat monitored intermittently rather than continuously³⁸

[This research summary includes information from the following leaflet produced by MIDIRS:

Informed Choice for Professionals No.6 - Epidural pain relief during labour

For details on how to purchase the Informed Choice leaflets go to the Informed Choice website.]

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