To induce or not to induce?

The policy of many hospitals in the UK is to induce labour if the pregnant woman is ten days over her due date. This may be decreased to seven days with older mums (>35) or increased to two weeks in some hospitals. This suggests that there are valid medical reasons to induce labour but this has not been proved through medical research. The guidelines issued by NICE state:

“Induced labour has an impact on the birth experience of women. It may be less efficient and is usually more painful than spontaneous labour, and epidural analgesia and assisted delivery are more likely to be required.”

In the UK, due dates are calculated by two methods – Naegele’s rule (introduced in the 1800’s) and ultrasound scanning. There is a lot of variability in the methods used for due date predictions; and also gestation times can vary from woman to woman. Several factors affect the accuracy of a due date: the length of a woman's menstrual cycle, her age, health, weight and the number of previous pregnancies all play a part. These factors, combined with the ‘overdue’ calculation, could easily lead to circumstances where the baby is not yet ready to be born, yet the mother feels obliged to undergo induction due to medical ‘rules’.

During natural labour, a number of different hormones are released by both the mother and the baby at different intervals, in different amounts and with different half-lifes. During an induced labour, synthetic hormones (normally synthetic oxytocin) are given via a continuous drip, rather than in a pulsatile manner. Drug-induced contractions can be longer, stronger and closer together than those experienced in natural labour, and can cause more pain in early labour than either a woman expects, or what she would have experienced if labour had been allowed to progress naturally. During an undisturbed labour, pain endorphins are released as labour progresses and these act as natural opiates which help the birthing woman to cope with the increasing pain of contractions. The use of induction drugs increases the need for pain medication which in turn increases the use of further interventions, including instrumental deliveries and Caesarean sections.

The results from an Australian study on interventions during labour in both primiparous (first-time mothers) and multiparous (given birth before) women between 2000 and 2002 demonstrate the effects of having an epidural for pain relief (Tracy et. al. 2007). Interestingly, the use of induction methods does not make a statistically significant difference to the birth outcome but the use of an epidural does. Instrumental and surgical births are greatly increased in both induced and spontaneous births when pain relief via epidural has been administered.

The choice of whether to be induced, and whether to accept medication for pain relief, should be discussed with both the mother and her partner before labour begins. Women often want to experience a natural birth but can change their minds during the course of labour, either due to medical advice, or because they firmly believe they need extra help. It is the role of the doula to remain calm during these conversations in the labour room, to remind the woman and/or her partner of her wishes, to suggest alternatives and lastly, to step back and allow the medical staff to do their job if a final decision has been made for pain medication. It has been shown that women respond to birth more positively if they feel that decisions were made with their full acknowledgement and informed consent.

References:

Neilson, J.P., Induction of labour for improving birth outcomes for women at or beyond term. Obstet Gynecol, 2007. 109(3): p. 753-4.

Dubreuil, V.L., Standard term of pregnancy. Midwifery Today Int Midwife, 2004(72): p. 51-3.
NICE, Induction of Labour, in www.nice.org.uk/CG070, N.C.C.f.W.s.a.C.s. Health, Editor. 2008.

Green, J.M. and H.A. Baston, Have women become more willing to accept obstetric interventions and does this relate to mode of birth? Data from a prospective study. Birth, 2007. 34(1): p. 6-13.

Tracy, S.K., et al., Birth outcomes associated with interventions in labour amongst low risk women: a population-based study. Women Birth, 2007. 20(2): p. 41-8.

Howell, C.J., Epidural versus non-epidural analgesia for pain relief in labour. Cochrane Database Syst Rev, 2000(2): p. CD000331.