Pain relief methods during labour would include non-pharmacological methods and pharmacological methods.
Non-pharmacological methods include meditation, acupuncture, music therapy and breathing exercises. These methods are of variable efficacy and varies from person to person. Increasingly, some patients are finding some pain relief in immersing themselves in warm water during the labour and for delivery.
Pharmacological methods include intramuscular pethidine, entonox (mixture of laughing gas and oxygen) and epidural analgesia. 1. Intramuscular pethidine works well for early part of labour but should be avoided in advanced stages of labour as it risks respiratory depression to the baby otherwise. 2. Entonox (or gas and air) is safe and its efficacy is variable, depending on individual. It is usually sufficient in the early stages of labour, however, it is may not be adequate when the pain becomes severe. The common side effects are drowsiness, nausea and vomiting. 3. Epidural analgesia provides the most effective pain-relief during labour of the 3 pharmacological methods.
It starts with an intravenous line. Epidural can be done with you lying on the side or sitting up. It involves an injection into the epidural space from the back and insertion of a cathether which provides an infusion of drugs to provide pain relief throughout labour. It is a highly effective and common pain relief method that can be safely carried out. Mobility would be limited hence it is a good idea to have during the active phase of first stage of labour or earlier if there is significant pain already. Food and drinks can be taken after the epidural has been inserted. If an emergency Caesarean section is required because of non-reassuring fetal status (or fetal distress) or poor progress of labour, it is usually performed under epidural analgesia. There are potential side effects associated with this method but serious complications are rare and such serious complications can be minimised further when anaesthetists experienced in epidural anaesthesia perform these procedures. Common side effects are usually temporary:
Numbness and weakness in the lower part of the body
Shivering (this can be distressing to some)Upper body itch occurs in up to 30%
Drop in blood pressure in 2% and it makes you feel nauseous and faint
Inability to pass urine - however, usually a urinary catheter is placed into the bladder and this is removed when you start walking about after the delivery
Mild bleeding and bruising at the injection site
Backache is usually temporary and due to bruising at the injection site. No evidence of long term backache. Other common causes of backache are pregnancy hormonal and physical changes, delivery process and breastfeeding.
Patchy block (i.e. while pain relief is felt in most areas, a specific area on the abdomen may not be as well blocked as other areas) and one-sided block occur in up to 5-10%
Epidural is associated with fever in labour, especially for long labour. Cause is not fully understood but appears to be independent of infection.
Only a fraction of epidural medications get to the baby. In the doses used, they are proven to be safe.
Occasionally, the baby's heart beat may drop especially when you are already in great pain. This is usually reversible with medication to temporarily reduce the contractions. Only occasionally is an emergency caesarean section required.
Epidural may prolong your labour, though only modestly. There is evidence that it can prolong the first stage of labour by 42 minutes and second stage by 14 minutes.
Epidural may increase the use of forceps and vacuum for delivery, probably more in those who are more numb and are unable to push well at the end.
But epidural does not increase the need for caesarean section.
Serious but uncommon side effects
Spinal headache that can last for about a week. The chance is less than 1 in 200. Should it be severe and persistent, an epidural blood patch would have to be done in the operating theatre.
High block causing breathing difficulties and rarely unconsciousness occurs in 1 in 2000
Total block failure may rarely occur and requiring re-siting of the epidural
Local anaesthetic toxicity occurs in 1-11 in 10 000, can cause seizures and cardiac collapse.
Nerve damage can be temporary or permanent.
Temporary damage causes a numb patch on the leg or foot, or a weak leg. This occurs in 1 in 1000 to 2000 women.
Permanent damage last more than 6 months and the chance is 1 in 24 000.
Meningitis occurs in 1 in 100 000
Abscess (infection) in the spine at the site of injection occurs in 1 in 50 000
Blood clot in the spine occurs in 1 in 168 000
Severe nerve damage including paralysis as a result of abscess or blood clot is 1 in 100,000
It is a good idea to decide on a strategy for pain relief during labour when you are still not distressed. In general, there are 2 main strategies.
The first strategy is to ask for epidural analgesia either just before or early during the active phase of 1st stage of labour (i.e. before the pain becomes significant).
The other strategy is to try and cope with the pain of labour with non-pharmacological methods, Entonox or pethidine injections first, with epidural analgesia as a back up if labour pain becomes unbearable. The advantage of this strategy is that you may be able to cope very well with labour pain without the need for epidural analgesia. The disadvantage of this strategy is that labour pain is often maximum at the advanced stages of labour, and asking for an epidural at that stage may not be feasible practically (e.g. delivery is anticipated within 30-60 minutes, and the lag time for an epidural to work [including time for anaesthetist to respond, perform the epidural, and for the medications to work] may exceed that).
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