As pressures grow to check the steady growth in the size of the health bill, the decision of the National Institute for Health and Clinical Excellence, Nice, to give all women the right to give birth by Caesarean section might look like a step in the wrong direction. Each Caesarean costs about £800 more than a natural birth and the rate of Caesarean sections in this country is already well above the rate that the WHO recommends, which is 10 to 15 per cent.

But Nice – whose new guidelines on the matter come into force next month – is caught in a dilemma. Worries about costs must be weighed against the mantra of patient choice, and throughout the world more and more women elect to have Caesarean births. Britain's Caesarean rates rose from under 3 per cent in the 1950s to 12 per cent in 1990-91, 23 per cent in 2003-04 and are more than a quarter today. In the US the rise has been even sharper, from 4.5 per cent in the 1960s to 31 per cent in 2007 and more than one in three today. Some parts of Europe like the Benelux and Nordic countries are behind Britain in this respect. But even there the growth in rates of Caesarean births is striking.

Britain is following a trend dictated by various forces. Rising average ages at which mothers give birth and rising obesity levels among pregnant women tend to prompt women to choose Caesarean sections as the safer option. Risk-averse doctors feel that performing a Caesarean section reduces the likelihood of being sued for medical errors. One of the main arguments in favour of natural childbirth – that it gets easier the more children you have – has also lost much of its force in countries where women increasingly don't intend to have a second child.

For natural childbirth campaigners, the new NHS guidelines will be disappointing. A few decades ago they seemed to be winning the argument. Now the trend in the other direction is likely to be accentuated by making natural or surgical childbirth purely a matter of choice. There is little they can do. Several years ago, the Journal for the Royal Society of Medicine wrote: "We cannot realistically expect rates of Caesarean section to decline greatly if at all." The same observation could be made today.