Epidurals reduce or eliminate the pain of contractions
Learning relaxation and breathing techniques does not reduce the need for an epidural in labour, a study shows.
More than 1,000 mothers-to-be took part in the Swedish trial, thought to be the first major analysis of the efficacy of such preparation for childbirth.
They attended one of two classes: the first taught natural coping methods, the other emphasised pain relief.
But the BJOG study found no difference in the use of epidurals between the women when they went into labour.
Just over half the women in each group ultimately opted for the spinal analgesia which reduces or eliminates the pain of contractions.
Some 70% of the women who had attended the natural childbirth class said they employed the psychoprophylaxis techniques they had learned, which included breathing and relaxation methods as well as ways of coping with pain such as positive imaging.
As well as there being no difference in epidural rates, which researchers saw as a useful measurement of perceptions of pain, the proportion of vaginal births and emergency Caesareans was the same between the two groups.
In the natural childbirth group, there was a slightly higher rate of instrumental births, involving forceps or a ventouse.
But overall the majority of women in both groups were satisfied with their birth experience, with the same small minority in both describing it as "negative" or "very negative".
"Our conclusion is that natural childbirth preparation with psychoprophylaxis does not reduce the need for epidural analgesia or improve the birth experience, when compared with the standard form of antenatal education," said Malin Bergstroem, a clinical psychologist at the Karolinska Institute who co-authored the study.
In the UK, the contents and availability of classes varies across the country. The majority are carried out by the NHS or the National Childbirth Trust (NCT).
Patrick O'Brien, a consultant at UCLH and spokesman for the Royal College of Obstetricians and Gynaecologists, said it was "only fair that women should be told the results of this study".
"It's almost accepted that these techniques might help but the evidence out there is not that strong. This is the first good evidence to compare the two approaches.
"I'm not suggesting discarding relaxation techniques completely. They could still help people feel more in control and more relaxed. But this research may temper the statements of the more pro-natural people."
Professor Cathy Warwick, general secretary at the Royal College of Midwives (RCM), said: "We believe that preparation for birth is an important component of delivering high quality maternity services.
"These classes can boost a mother and her partner's confidence. Classes here do more than focus on breathing and relaxation techniques, they allow mothers to develop a support system and learn about becoming a parent."
Belinda Phipps, head of the NCT, said: "This limited study in Sweden compares two slightly different types of antenatal education and does not look at the more common situation in the UK which is no or limited antenatal preparation.
"Testing to see whether breathing and relaxation techniques alongside antenatal preparation have an effect on birth outcomes is a tall order - they are only one small part of antenatal education."