Epidural analgesia in childbirth has been the subject of much research and auditing during the past thirty years. Indeed, it would be difficult to find another medical procedure which has been so well documented. When managed properly, epidural analgesia has proved to be remarkably safe - as, indeed, it must be. It is true that there are some side effects and complications but these are rarely serious and largely preventable.

For many years, epidural local anaesthetics were used during labour in the same doses that are used for surgery. This kind of epidural is certainly very effective in blocking out pain, but it usually blocks out everything else as well!. Consequently the mother feels colds and numb, half paralysed and hardly aware that she is having a baby at all. She is also more likely to need a urinary catheter and an instrumental delivery because she has no feeling, or urge, to push.

There can be little doubt that side effects such as these have tarnished the reputation of epidurals in some places. more recently, however, several centres have recognised that such a "blunderbuss" approach to epidurals is quite unnecessary and that most side effects can be overcome simply by reducing the dose of local anaesthetic.

During the last few years, epidural opioid drugs have also been used in some centres instead of local anaesthetics. Epidural opioids behave quite differently from local anaesthetics and do not interrupt, or "block", nerve transmission. Accordingly, they do not cause muscle weakness or interfere with sensation other than pain. Unfortunately, while epidural opioids are very effective in relieving postoperative pain, most studies have found them to be inadequate by themselves during labour. When combined with local anaesthetic, however, they are much more reliable. Moreover, the addition of an opioid permits further reductions in local anaesthetic dosages to occur. Consequently, the incidence and severity of local anaesthetic side effects are also reduced. For these reasons, low - dose epidural local anaesthetic-opioid mixtures are becoming more and more popular.

There are several important benefits offered by epidural analgesia. They provide extremely effective pain relief without causing sedation or mental confusion. It is also very easy to use the epidural if an instrumental delivery or caesarean section becomes necessary. In addition, there are certain complications or conditions in pregnancy where an epidural is recommended for medical reasons. High blood pressure, premature birth, twins, vaginal breech delivery and trial of labour after a previous caesarean section can be examples of these.

There are now many studies to show that epidurals reduce, or reverse, practically all of the stress-related responses of the body to pain in childbirth. Thus, breathing returns to normal so that the effects of hyperventilation ( fatigue, giddiness, sensation of 'pins and needles') go away; the muscles begin to relax; the blood pressure falls, and the blood chemistry improves. There is also evidence that the workload of the heart and the body's oxygen requirements are reduced, and that blood flow to the uterus may be improved.

Finally, when an epidural catheter is in place it is very easy to use it for other procedures- instead of having to have a general anaesthetic. A caesarean section or instrumental delivery are obvious examples. An epidural can also be used to remove the placenta if it does not come away by itself (1-2% of all deliveries), and to provide pain relief after delivery ( eg. after caesarean section, bad piles, and backache). It can even be left in place overnight and used the next day for having a tubal ligation.