Researchers have said that the hormones in the oral contraceptive affect the type of guy a woman is attracted to. 

So if she was on the Pill when they met, she might get a shock when she comes off it - and ought to have a trial run before she settles down, the Daily Mail reported. 

But other experts have urged women not to throw away their packets of the Pill, insisting that taking the risk of becoming pregnant is an extreme way to work out whether a man and woman are suited. 

To assess the effect of the Pill on women's taste in men, Dr Craig Roberts of Stirling University questioned over 2,500 mothers from around the world on how happy they were in their relationships. 

Some had met their partners while on the Pill. Most, but not all of those surveyed were still with the fathers of their children. 

Those who had been on the Pill reported less sexual contentment than the other women. 

They found their husband or boyfriend less attractive and less exciting in the bedroom, according to the study. 

But the Pill users rated their partners more highly as far as other aspects were concerned, like seeing them as more faithful, more supportive and better providers. 

Overall, these positives apparently outweighed the less exciting sex lives, with relationships lasting two years longer on average if the woman had been on the Pill at the start. 

It is believed that the hormones in the Pill tend to sway women away from 'macho' men who provide the thrill of a fling towards more sensitive types who will be a better bet in the long-run. 

"The implications of our study seem to be that by changing your hormone profile through using the Pill, you might shift your preference away from "cads" in favour of "dads"," Dr Roberts said. 

He insisted that his results are based on the average responses of thousands of women, and not every woman on the Pill will experience the same effects. 

"Choosing a non-hormonal barrier method of contraception for a few months before getting married might be one way for a woman to reassure herself that she's still attracted to her partner," he added. 

The study has been published in the journal Proceedings of the Royal Society B.