Experts in the United States believe the demands of modern life are to blame - leaving women with little time or energy.

Fifty years ago, most women were stay-at-home mums with more free time. Few had jobs and television sets were rare.

People don't have as much sex as they used to Dr John Bancroft, Kinsley Institute

Today, many women hold down jobs while also raising children. Any spare time is often spent shopping, working out in the gym or watching their favourite television programmes.

Researchers from the Kinsey Institute said women now have less time for sex.

They found that 42% of women who cohabit with male partners have sex two or three times a week. This compares to just one in three married women.

Less time

The researchers said that while figures from the 1950s are not directly comparable they were higher.

"People don't have as much sex as they used to," Dr John Bancroft, the institute's director, told the Daily Mail.

"Couples are often weighted down by double careers and childcare, and by the time people have been to the shopping mall and watched all the television they want, there is not much time for sex.

"We live in an age where there is little unfilled leisure time. Sex used to fill that gap."

The researchers carried out a survey of 853 women between the ages of 20 and 65.

The found that fewer women may have sexual problems than was previously thought.

The survey suggested that just one in four American women are "significantly distressed" about their sex lives.

This compares to a 1999 study which suggested that almost half of all women suffered from sexual dysfunction, such as a lack of interest in sex.

The researchers said the sharp difference may be due to the fact that previous studies have only looked at the physical aspects of sexual dysfunction - problems with arousal and orgasm.

Sexual problems

The Kinsley Institute team said emotional and mental aspects need to be taken into account when trying to determine levels of sexual dysfunction in women.

They said women's sexual satisfaction, her general emotional well-being and her emotional relationship with her partner are important factors.

"This study emphasizes the importance of non-physiological components of sexuality as well as the general importance of mental health," said John Bancroft, director of the Indiana University-based Kinsey Institute.

"It's not conclusive, but it counterbalances what I believe to be the rather extraordinary conclusion that 43% of women suffer from sexual dysfunction."

The Kinsey study, which will appear in the June issue of the Archives of Sexual Behavior, was a random telephone survey of women who had been in a heterosexual relationship for at least six months.

Is your life too busy to fit sex in? Do you think we are having less sex?

Your reaction

I was starting to feel like the only woman without a sex drive until I realized that half of my friends feel the same way. But then I realized that I have sex pretty often; it's just that I don't feel as into it as my boyfriend. I work full time, clean the house, do the laundry, take care of the animals, cook and wash dishes. So, yes, after all of that I'm tired and the last thing I feel is sexy. However, I am able to get out of bed early to exercise. So maybe I should stop cleaning for an hour every day and make time for my loved one and have sex. Maybe, then, it's all about making sex a priority, which it really should be. I mean, it's certainly not everything, but it's a pretty big deal.
Bridget, USA

Stress has a knock-on effect on libido Julie, UK

I don't think it's true to say women are too busy for sex, it's not as simple as making a choice between sex or TV. If you speak to most women nowadays, they are holding down stressful jobs, managing a household and possibly bringing up children, and by the time they have done all that they don't have enough energy to do anything except slump in front of the TV for a couple of hours then fall into bed and go straight to sleep. Stress also has a knock-on effect on libido, which is probably a problem our mothers didn't face in the 1950's when there were fewer demands on their time.
Julie, UK

Why are we working from the assumption that sex 3-5 times a week is normal, and that wanting anything less is not? I feel plenty close to my partner, and feel there are plenty of other ways to express that besides sex. It's the relationships that don't exist outside the bedroom that are in real trouble. I think this sex-focused attitude to relationships is plain silly. Has anyone wondered whether it is the media's obsession with the quality and quantity of everyone's sex that's putting people off?
Gina, England

TV is one of the most successful contraceptives these days Pete, England

This could be describing us! My wife's ratio of TV watching to having sex must be worse than 20 to 1. I guess that the TV is one of the most successful contraceptives these days. When it breaks, I certainly won't be in a hurry to get it fixed! Perhaps I won't renew the licence.
Pete, England

I have been married for almost three years and we have no children. Our sex life is as active if not more so than it was when we were first married. We have sex four to six times a week. Frankly, I think that excuses about sex are an easy way to get out of facing the fact that most couples have less sex because they do not have a strong emotional connection. Is there a survey for that?
Anne, USA

Our role in the bedroom is different. Men expect us to hold down 40 hour a week jobs, clean the house, make five star meals and take care of the children and at night become a porn star. I just want to be mentally stimulated, and have a true feeling of being loved. Not sexed. If men were more compassionate they wouldn't complain about having sex 2-3 times a week, they are lucky they get it at all.
Angela McCullough, USA

Sex is a good way to relax the mind after a busy day at work! Michelle, UK

If I'm honest, when my partner neglects me in terms of affection or support, I generally feel put off from having sex with him. I am very supportive towards him but sometimes, I can't get close to someone who just takes advantage and prefers to 'take' rather than 'give'. As for being too busy, I feel that sex is a good way to relax the mind after a busy day at work!
Michelle, UK

I have found that women want to make love a lot more when they are treated with respect and listened to. Just treat them like a friend. My fiancée is very enthusiastic about having an early night unless she's waiting up for Sex and the City. Anyone else see the irony there? Anyway, even though frequency is above average now, I'm sure it will fall off with time as work places ever increasing demand on our time. But then it can be even better when you have the time. It's about quality, not quantity. I think the survey is a waste of time as it is too general.
David, USA/Ireland

The only competition for sex is sleeping and eating Lisa, Canada

Being busy is a silly reason for not having sex. And so is watching television. The only competition for sex is sleeping and eating.
Lisa, Canada

My TV has just broken so I will be interested to see if my girlfriend and I have more sex. Depending on how it goes I might not get a new TV.
Justin, UK (ex Oz)

We're seriously asked to believe that "a random telephone survey of women who had been in a heterosexual relationship for at least six months" are too career-minded to have sex? Come on! What were they doing on the phone in the first place, preparing Powerpoint meetings? Why not put the phone down, go out with some friends, and find someone you fancy?
Steve, London UK

Our jobs are very demanding, but we set our alarm an hour early, or have a quickie before tea, anything to make sure we don't go a day without... once you decide that's what you want to do, it's very easy and great fun!!
Bunny, UK

These studies are carried out mainly by male researchers and that's why women who don't desire sex as much as their male partners are branded as "sexually dysfunctional". We women are not automated, hormone-driven creatures, and find it difficult to feel affectionate towards our men if they neglect us and only expect us to fulfil practical purposes outside the bed, like taking the kids to school and cooking supper.

This feeling to me is "absolutely normal" rather than "dysfunctional". Shame the researchers haven't looked at how male attitudes have changed since the 1950s in terms of courtship, respect and politeness, as it could have resulted in some interesting answers for them. Has anybody ever heard of a "sexually dysfunctional" woman in the courtship stage? Not many, I should think...
Eva W, UK

After having worked full time since 1969 I took early release. What a difference! I now get a full night's sleep, I no longer have to fight my way on and off public transport, and guess what? I have re-found my sex drive, much to my husband's delight.
Hazel, UK

Everyone is too busy for sex but there are differences in the way it's viewed in men and women. If it's a woman, people are sympathetic, and say of the husband "Doesn't he see how hard she works?" If a man is too tired, people think there's something wrong with him, and that the woman involved deserves better.
Selim Miah, England

We probably do it 3-5 times a week. It is partly tiredness after we both work long days and play evenings and weekends. Partly that is just the amount we are both happy with! Must be hard to compare to historical averages though - how many people are honest on sex surveys?
Lorna, UK

My husband and I have sex at least 2 times a week and sometimes we actually go without for at least 2 weeks. It is not that we don't love each other or are sexually dysfunctional. It is simple we both work 45-50 hours a week, I clean the house and cook every night when we get home and to top it off we have 2 boys under the age of 5. So, it is really the factor of time. Although we try to have time to ourselves, it is mostly cuddling and watching movies on the couch and talking about what we are going to do for a vacation... things families should do and think about. Sex is not everything... being understood and having a friend in the opposite sex which you are growing old with is. Remember that one day sex may be an impossibility and that conversation and cuddling will be the only thing left.
Addy, USA