Research on Hypnosis for Childbirth
Some Comments on a Recent Systematic Review
Copyright (c) Donald Robertson 2010. All rights reserved.
See the related blog category for other articles on hypnosis and childbirth.
A systematic review entitled ‘Hypnosis for pain relief in labour and childbirth’ published by Cyna, McAuliffe and Andrew of the Dept. of Anaesthesia in the Adelaide Women’s and Children’s Hospital in Australia, is currently the most recent survey of hypnosis for managing pain during childbirth. It was published in the British Journal of Anaesthesia in 2004. The authors identified five randomised controlled trials (RCTs) and fourteen non-randomised comparisons (NRCs), studying 8,395 women in total, where hypnosis was used for pain relief during labour. They carried out a detailed critical appraisal and statistical analysis of the results of these earlier studies, by different researchers in Britain and America. This short piece will attempt to summarise some of their main findings and comment upon them.
As the authors observe, hypnosis has been used in relation to childbirth for more than a century. Indeed, James Braid, the founder of hypnotherapy reported a case where hypnotic suggestion was used to induce early labour, to prevent complications in a particular case, in a book published in 1853, almost a century-and-a-half ago. Soviet researchers used hypnosis and related methods to manage pain and other problems related to childbirth quite extensively in the first half of the 20th century.
The authors of this review cite previous research demonstrating the benefit of other psychological interventions such as “continuous support” during labour, which have been found to reduce the need for analgesia, operative birth, and to reduce reported dissatisfaction with childbirth experiences. The fact that other psychological approaches are known to be of benefit lends indirect support to the use of hypnosis, as it demonstrates that, in principle, the mind plays an important role in the experience of childbirth and that this can be influenced positively by saying and doing certain things. They also mention studies examining the attitudes of anaesthetists to hypnosis for obstetrics. For example, one survey of South Australian anaesthetists cited in this review reported that nearly half of them considered hypnotherapy to be of potential value.
A number of well-known psychological approaches to natural childbirth exist, all of which are derived, to some extent, from early Soviet research on hypnosis for labour carried out by Platonov, Velvovsky and others. Slightly later than the Soviet hypnotists, in Britain, Grantly Dick Read developed his influential ‘Childbirth without Fear’ approach, without hypnosis, using education, reassurance, and muscle relaxation. This was followed, in France, by Fernand Lamaze’s method, which was directly based upon the Pavlovian approach developed in the Soviet Union. These and other methods use a variety of techniques, based on slightly different conceptualisations of the problem. However, they report similar results and share many obvious common factors such as the use of education, suggestion, and relaxation, in different forms.
The authors of this systematic review use sophisticated statistical techniques (“meta-analysis”) to pool data from earlier studies published by different authors and compare the results. Before doing so, they evaluated the quality of the research and rejected studies which failed to meet their critical appraisal criteria. They reported two main statistical findings based on this analysis. First, they calculated the reduced number of women making use of pharmaceutical pain relief during labour as a result of hypnosis, based on three different studies with a total of 142 participants. This was reported as an overall mean ”risk ratio” of 0.51. (The 95% confidence interval was 0.28-0.95, for those familiar with health statistics.) In plain English, the risk ratio means that women having hypnosis, on average, were half as likely to feel they needed chemical anaesthetics during labour, compared to women who didn’t receive any hypnosis. In other words, of 74 women who were hypnotised, across three studies, only 28 required pharmacological pain relief (38%), compared to 50 out of 68 (74%) in the control (not hypnotised) groups.
The second result analysed was the reduction in the number of women who required “labour augmentation” with oxytocin following hypnosis, based on two studies with 102 participants between them. This was reported as a risk ratio of 0.31, which means that on average women who used hypnosis to prepare for labour were nearly 70% less likely to require augmented labour than normal, i.e., compared to women who didn’t use hypnosis (95% CI=0.18-0.52). In other words, of 52 women who were hypnotised, across two studies, only 11 (21%) required labour augmentation, compared to 35 out of 50 (70%) in the control (not hypnotised) groups.
The authors report that one of the earlier studies they looked at, by Harmon et al., found that “spontaneous delivery”, i.e., “normal” childbirth without induced labour, caesarean, etc., had a risk ratio of 1.67, meaning it was 67% more likely among women who had been hypnotised, based on a sample of sixty women (95% CI=1.13-2.67).
In addition to these beneficial results, Cyna et al. found no reference whatsoever to any adverse or negative effects of hypnosis in obstetrics in any of the studies they reviewed. A further search identified two isolated cases but these seem exceptional and there’s no evidence the problems were related to the hypnosis used. They conclude, “It is interesting to note that, despite differences between trials in the timing and number of hypnosis interventions reported, outcomes are consistently in favour of hypnosis.”
Cyna, A.M.;McAuliffe, G.L.;Andrew, M.I. (2004). ‘Hypnosis for pain relief in labour and childbirth’, British Journal of Anaesthesia, 93(4), 505-511.