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or many women, childbirth will be the most painful experience of their lives. But while labor pains are inevitable, there exist good and effective methods for women to relieve pains.

As a pregnancy approaches term, the womb begins to contract, and what were previously painless Braxton-Hick contractions transitions into intense labor contractions.

Pain is debilitating when it occurs repetitively and insists on being attended to by exerting various bodily changes in the mother.

First affected is the workload her heart has to bear, which increases blood pressure and reduces placental blood flow. This may be followed by uncoordinated uterine contractions, which can subsequently lead to prolonged labor and a greater chance for fetal distress.

As such, any effort made to lessen labor pains would intuitively improve maternal and foetal outcomes, and consequently shorten the expected duration of labor.

There are two methods of reducing labor pains: non-pharmacological and the pharmacological methods.

For non-pharmacological methods, the most effective element is continuous labor support. Whether it be the partner, relative or nurse, the presence of someone to support the mother has been shown to shorten labor duration, reduce requests for pain-relief medication (analgesia) and reduce assisted instrumental delivery or Caesarean sections.

Other methods include acupuncture, hypnobirthing and water baths. Ineffective methods of pain relief include massage therapy, touch therapy, aromatherapy, audial analgesia and transcutaneous electrical nerve stimulation (TENS) '€” nerve stimulation by an electronic device to reduce pain.

There are three available pharmacological approaches to reducing labor pains '€” Entonox gas analgesia, Pethidine injections and Epidural analgesia.

Each option has varying effectiveness, which are measured using a Wong-Baker Visual Analogue Scale (VAS) system '€” the levels of pain experienced are measured subjectively along a scale ranging from '€œzero'€ to '€œ10'€, a pain-score of '€œzero'€ being completely pain-free, while '€œ10'€ reflecting the worst possible pain.

The first option, Entonox, is the mildest. Also known as laughing gas, it is a mixture of nitrous oxide and oxygen and exerts a calming effect to take the edge off pain, rather than completely blocking it out. Entonox typically reduces the pain score by one or two points.

The second option, Pethidine, is an opium-derived drug that functions as a painkiller and an anti-spasmodic, which helps the mother relax. Pethildine is administered via an injection every four to six hours. Pethidine injections can be given in multiple doses, but causes drug accumulation in the body and thus cannot be administered if delivery is anticipated in the following four hours because this risks the sedation in the new-born and could require neonatal resuscitation if performed. Pethidine usually reduces the pain score by four to five points when used appropriately.

The third option, epidural analgesia, is used extensively for labor pain management.

Epidural analgesia involves inserting a fine and flexible plastic tube containing a local anaesthetic solution into the space surrounding the spinal cord nerves to greatly diminish or remove the pain. This approach typically reduces pain scores by eight to nine points.

Increasingly, women are completely pain-free after an epidural. However, they can still opt for an epidural if the side effects of other medications are intolerable or if their labors are advanced and Pethidine cannot be administered safely.

Mothers with medical conditions, such hypertension or preeclampsia risk of suffering a stroke, can receive external benefits from an epidural.

An epidural would blood pressure levels and reduce this risk. In addition, with improved placental blood flow comes a reduction in the risk of fetal distress during labor and delivery, especially in cases of growth restriction.

However, patients with clotting problems due to medical conditions, back skin infections, spinal problems, or a history of spinal surgery and severe cardiac disease are unsuitable candidates for an epidural.

Some common side effects are numbness and weakness of the lower body and legs, vomiting, shivering, a transient decrease in blood pressure, difficulty with passing urine, one-sided block (where the mother experiences pain on only one side of the body), as well as the rapid progression of labor, such that delivery becomes imminent. Serious side effects like seizures and respiratory arrest are very rare.

Apart from the observed side effects of epidurals, the use of an epidural has spawned many myths. These include the belief that epidurals cause long-term backaches in the mother, harm the baby or increase the risk of requiring a Caesarean section. None of these are true.

While more than half of pregnant women suffer from antenatal backache, the use of an epidural was not found to contribute to the cause or worsening of backaches.

Instead, the pain was due to the physiological changes associated with pregnancy, such as poor posture, spinal anatomical changes associated with pregnancy, hormonal changes and water retention.

Mothers are advised to return to previous exercise regimes, especially core body strengthening exercises after delivery, so as to reduce the risk of chronic backache in the long run.

In a study comparing epidural administration before and later into established labor, it was found that patients who had an early epidural experienced a shorter duration of labor and did not have an increased risk of progression to Caesarean section. It was also found that the babies delivered had better health assessment scores (Apgar scores), apart from superior pain relief.

Researchers believe that shorter labors may be due to the relaxation of the pelvic floor muscles when the patient is pain-free, allowing easier passage of the baby through the birth canal.

Labor is often an unpleasant experience for women. But while discomfort and pain are unavoidable, it is unacceptable that a mother should suffer in agony while safe and expeditious methods of pain relief are available. After all, as long as a mother understands the pain relief methods available and their respective pros and cons, she should be allowed to savour her birth in a comfortably and safely.

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The writer, a consultant obstetrician and gynaecologist at the Gleneagles Hospital, was previously an adjunct assistant professor in the post-graduate DUKE-NUS Medical School. For more information, visit arthurtsengwhs.com.