It can be fun, dangerous, a total high and despite the fact that it can also break your heart, more and more women are doing it. It's that uninvolved liaison with a guy you go to bed with, but aren't committed to. Your one night stand

It wasn't always this way - even a generation ago, casual sex was relatively unknown for women. Men could sleep around and be regarded as 'sowing their wild oats' without a hint of criticism. But a woman who had casual sex was, and often still is, more likely to be labelled a 'slag' and seen as 'unnatural'.

In fact, it isn't necessarily natural for women to only want committed or involved sex. Yes, when we get broody we're likely to head for a stable relationship in order to get support for parenting, but geneticists now believe that in general, girls and guys are equally up for quick and uninvolved liaisons in order to spread their seed around to best effect.

The idea that women 'shouldn't' when men 'can' isn't instinctive at all. It comes from the fact that over the millennia, society has closed ranks to discourage women from casual sex. Dominant males, keen to ensure that it was their baby their women was bearing and not their mate's, have traditionally policed female sexuality, putting on the legal, moral and social pressure. Result - we feel guilt where the guys don't.

So why the change?
Casual sex is now more acceptable than it was because nowadays women have the freedom and opportunity for uninvolved lovemaking; we meet men through work, through friends or even through the Internet. We also have easy access to contraception and protection, making it far safer to have sex with no nasty repercussions.

Women also have fewer inhibitions nowadays. In particular, female drinking figures are rocketing, and alcohol makes it much more likely that we'll have sex with a companion even if we've only known them a few hours.

Plus, we have more motivation. Women are living an increasingly demanding life and need sex to lower our stress levels, to comfort us, to make us feel more secure. If we haven't got a regular partner, we see no reason not to take an 'irregular' one. Plus, that avoids the problems and responsibilities that only a committed relationship brings.

It's also that nowadays, we women are more up for excitement, adventure and risk. We want to feel alive and the rush of sex with a stranger gives us that feeling, stimulating our sympathetic nervous system, pumping up our adrenaline and putting our bodies on a sense of high alert. No wonder casual sex can feel more exciting than a regular Saturday night session with a regular partner.

All of which explains why, in a survey in the States commissioned by the Oprah Winfrey Show, 50 per cent of respondents said that casual sex was worth it. They thought it exciting, enjoyable - and a statement of their sexual identity, a reflection of the fact that as a 21st century woman, they wanted to be free to have sex when and with whom they wanted.

The backlash
So that's the good news. Sadly, here's the bad. The other 50 per cent of Oprah respondents thought that casual sex wasn't worth it - and 80 per cent of them have had regrets. It isn't the morality, it isn't even a feeling of shame. The main reason that casual sex may not deliver is that we often want more than just the instant hit it offers - and even if we didn't want more when we started, we do when we finish.

Particularly if we're older, particularly if we're broody, particularly if we're using casual sex as a stopgap until Mr Right comes along, we can find it difficult to walk away from someone we've had sex with - even when he's a stranger we've only just met.

This isn't just conditioning; that we've been brought up to believe in the concept of love and sex going hand in hand. It's that physiologically, sex creates a flood of hormones that naturally create a bond. Oxytocin (the same hormone that women release while breastfeeding) makes us feel close to a partner and dopamine makes us feel content in his company, both of which are released during sex.

So before casual sex we were clear-headed, sure that we could walk away with no regrets. After sex we may suddenly feel involved, emotionally intimate whether we like it or not - and whether it's wise or not.

There is, of course, an added sting in the tale - that our partner may not have suffered the same shift of emotions. He, with his different conditioning, may be able to ignore the prompting of his hormones and remain uncommitted. We feel betrayed that he's walking away. He feels wrong-footed that we're reneging on the original, uninvolved deal.

Result? Casual sex may simply be a bad idea for us because it can create feelings that we can't control - not to mention needs that we cannot meet.

Should you or shouldn't you?
So is casual sex something that you personally can enjoy and benefit from? It's likely that deep down you already know the answer - your gut reaction will tell you if it's going to be right for you.

But if you're in any doubt, think about these questions. A 'yes' answer suggests that casual sex can work for you, a 'no' answer that - at this point in your life - it won't.

• Have you ever been able to have sex for the sheer pleasure, even if you weren't involved with your partner? If not, you're likely to find casual sex uninspiring. But if so, casual sex can give you a high quality, high sensation experience.
• Does risk and insecurity make you excited rather than uncomfortable? If not, you may be so ill at ease that you won't enjoy sex. But if so, casual sex will increase your passion.
• Do you feel positive about friends or colleagues who have had casual sex? If not, then casual sex may make you blame yourself. If so, then casual sex is unlikely to dent your self esteem.
• Are you really responsible about contraception - even in the heat of passion? If not, you risk pregnancy or infection. If so, then you'll stay safe.
• Are you currently feeling high in self-confidence and sure of yourself? If not, you may get over involved with a casual partner and so get hurt. If so, then you're more likely to be able to handle a casual liaison.

Making it work for you
The bottom line here is that casual sex can be wonderful. But in the wrong context then it can result in more long-term pain than pleasure. So, finally, some tips on how make sure that it works for you.

1. Have casual sex for the right reasons - short-term pleasure, an ego boost, a sign that you're in charge. Never see it as a way of snaring your man.
2. Don't have casual sex when you've been drinking or when you haven't got protection; both are sure-fire routes to regrets.
3. Never blame a casual partner for treating the relationship casually - that was the deal, remember!
4. If in the morning you feel over-emotional, desperate and clingy, remember it's your hormones kicking in - do all you can to calm down and make a dignified exit.
5. If casual sex works for you, enjoy! If it doesn't, then steer well clear, and wait for Mr Right, not Mr Right Now!

Further reading
Brief Encounters - the women's guide to Casual Sex by Emily Dubberley, priced £10.99 from Fusion Press