What is it?Pethidine is a narcotic, controlled drug, which was introduced in 1939. It's most commonly given intramuscularly by injection into the thigh or buttock, although it can also be administered intravenously. It takes around 20 minutes to take effect and lasts for 2-4 hours. It can be re-administered, but as it affects the baby, you should be wary of having repeated doses.
How will it make me feel?Many mums-to-be have reported that although pethidine helped them relax, by making them sleepy, it didn't relieve the pain. Therefore they felt out of control during labour. However, as it can alter mood, it can sometimes work very well by enabling women to unwind and get some rest, while allowing labour to continue by relaxing the muscles of the cervix and womb. Different doses are given depending on weight, stage of labour and degree of discomfort, some women prefer to have 'half a dose', so they don't feel too sleepy during labour.
Does it give effective pain relief?Talk to a group of mums and they'll each have a different answer. It can depend on when it was given and the amount administered. The normal dose is 50-100mg, which is only 1-2ml. Many women find it more effective when the contractions aren't at their strongest, that is, closer to the beginning of the first stage. But this raises the problem of what to do once the pethidine has worn off. To be lying down in labour from such an early stage isn't ideal and can slow things down. However, it's also important to pace yourself, to be leaping out of bed in early labour and striding around the room will leave you feeling exhausted. Some women do have long labours, and despite using methods such as breathing techniques and soaking in a warm bath to relief the pain, they need something to help them rest, which is where pethidine is useful.
How does it affect the baby?It crosses the placenta and can make the baby sleepy, even after the birth, which may be serious if the injection is given close to the birth itself. Some babies with breathing difficulties will need an injection to reverse the effects of the pethidine. Others are slow to suck as a result of the pethidine and can have difficulties breast-feeding in the first few days. There's also some evidence to suggest that newborns who receive an opiate drug through their mum's bloodstream may be at an increased risk of addiction in later life.
The advantagesPethidine can be given by midwives, so is quickly available, unlike an epidural, which has to be sited by an anaesthetist. Tension and anxiety can sometimes hold back labour, and a small dose may be just enough to help you relax. For some women, it's a really effective form of pain relief.
The disadvantagesApart from the effect it might have on your baby, you may feel out of control if you feel sleepy but still in pain. It can also be difficult to judge when to use pethidine, as it shouldn't be given within two or three hours of the birth. One of the potential side effects is that it can make you sick, although an additional drug can be given to help prevent this. Another downside is that you'll probably be restricted to bed as you'll feel so sleepy, and you shouldn't use a birthing pool.
Anne Richley, midwife.