Rates of caesarean section are a cause of concern worldwide, although the problems vary according to the setting. In many poor countries, mostly in Africa, where average rates are 2%, caesarean section is underused because of lack of facilities and trained personnel.1 In other developing countries such as ones in Latin America and eastern Asia, incidence is 30% of all births or higher, even though large sections of the population lack access to basic obstetric care, while in developed countries it has steadily risen to about 20–25%.1 Despite such big differences between countries, the modifiable causes of rising caesarean section rates and what to do about them are unclear.

In this week's BMJ, a randomised controlled trial by Montgomery and colleagues looks at the effect of two computer based decision aids compared with usual care in pregnant women who have had a previous caesarean section.2 One aid provided structured information about possible …