Giving women more information about the type of birth they could have may avoid around 4,000 Caesarean sections a year in England and Wales, scientists say.
One in four UK births is by Caesarean section
A UK team found women who had already had one section were less likely to choose another if they used a computer programme to help make their decision.
Researchers say the system also reduced the anxiety of women, which can create problems during and after delivery.
The study is published in the British Medical Journal.
Rates of Caesarean section are increasing in the UK - from 9% of births in 1980 to 23% now.
Although they can be desirable, Caesareans can increase the risks of complications to the baby and the mother, particularly for future pregnancies.
The researchers from the Universities of Bristol and Dundee looked at 742 women who had previously had one Caesarean section.
The women in the study were split into three groups, receiving either traditional care, or using a computer-based information programme telling them the risks and likely outcomes of different delivery methods, or the more detailed "decisions-analysis system".
The decisions-analysis system asked the women what value they attached to the possible outcomes of the different delivery methods, and then gave them a "preferred option" based on their answers.
The women then discussed this option with health professionals, and 37% of those using this detailed analysis system had a vaginal birth.
This compared to 30% of the women receiving the usual care and just 29% of those using the other computer information programme.
Professor James Walker of the Royal College of Obstetricians and Gynaecologists, said this was an interesting study which could have exciting implications.
He explained: "It is very important to get information to women to help them to make a decision, so anything that improves their ability to get that information is a benefit."
He said around 75% of women such as these, who have already had a previous Caesarean, could have a successful natural delivery for a subsequent pregnancy.
He said decision aids were a good first step but that more work was needed to understand why women were being dissuaded from having natural births.