More than a third of women in the UK are not interested in having sex, a study has found.

Researchers conducted a survey of 12,000 Britons, asking them about their libido and attitudes towards sex.

Some 34 per cent of women admitted to not wanting sex, while the same was true for just 15 per cent of men.

Women also revealed they struggle to get aroused, had trouble having orgasms and found it difficult to enjoy sex.

Sara Collins found her sex drive dwindling after her first baby. By the time a second arrived she and her then-husband Graham were sleeping in separate rooms (right, Sara and Graham Collins are pictured on their wedding day; left Miss Collins today)

Most people grouped into a 'low interest' category (80 per cent) were married or living with their partner, the study showed.

Sara Collins found her sex drive dwindling after her first baby. By the time a second arrived she and her then-husband Graham were sleeping in separate rooms.

They ended up splitting last year as a result and she says she is ‘no longer interested’ in making love.

‘When we were together I thought my husband was fine with our no-sex marriage,’ she added. ‘Turns out that he wasn’t.

‘It seems you’re supposed to want sex like you’re 17 all the time. But as I got past 45 it just wasn’t something that bothered me.’

Miss Collins, 50, a receptionist from Lancing, West Sussex, said: ‘Before we had children we would make love three or four times a week. But by the time I had our third child I was 39 and physically repulsed by my body.

'There was nothing I could do to shift the excess pounds. By the time I’d accepted it, I was in my late 40s and experiencing the perimenopause. I had hot flushes, was irritable and I couldn’t bear my husband near me.’

Researchers from the University of Glasgow analysed sex life questionnaires from a total of 12,132 people in the UK, between the ages of 16 and 74.

Each was asked about their experience of STIs, unwanted pregnancy, being coerced into sex, their physical enjoyment of sex and their attitudes towards it.

Overall, 47.5 per cent of women were deemed to have 'poor sexual health', which included emotional experiences as well as physical problems or illness.

In comparison, the rate was just 17 per cent among men. The research was published in the medical journal BMC Public Health.

Miss Collins said of the study: ‘I don’t think it’s surprising at all. I have one friend who hasn’t had sex in over ten years. However I think men will find these statistics quite shocking. Men put an awful lot more weight on a sexual relationship than women.

‘The most important thing for couples to do is communicate. If my husband and I had been a lot more open about how he was feeling I think we could have got some help or counselling.’

HOW DO MEN'S AND WOMEN'S EXPERIENCES OF SEX DIFFER IN THE UK? (Survey of 5,000 men and 7,000 women aged between 16 and 74; 2010-2012) Category Men (%) Women (%) Lack interest in sex 15 34.1 Don't enjoy sex 4.8 12.1 Anxious during sex 5.4 5.2 Physical pain during sex 1.8 7.4 Lack of arousal 3.1 8.2 Trouble experiencing orgasm 9.2 16.3 Premature orgasm 14.9 2.3 Erection problems or vaginal dryness 12.1 12.2 Have avoided sex 11 13.5 Dissatisfied with sex life 11.6 11.2 Diagnosed with an STI in past 5 years 4.2 4 Feel at risk of catching an STI 4.1 2.7 Feel at risk of catching HIV 3.5 2.6 Had unprotected sex with 2 people at once 6.7 5.1 Had unprotected sex first time with most recent partner 15.2 13.4 Made to have sex against your will, since age 13 1.4 10.3 Other person was 'more willing' to have sex when you lost your virginity 4.4 16.2

The results showed that women were less likely to want or enjoy sex and more likely to have been pressured into having it.

WHY DO SOME PEOPLE HAVE LOW SEX DRIVES? A low sex drive is known as a loss of libido. Past research has suggested it affects nearly half of all women at some point in their lives, and it affects many men, too. It is often linked to relationship issues, stress or tiredness, but could also indicate an underlying health problem. Sex drives vary from person-to-person with no libido being 'normal'. However, if it is affecting your relationship, it may be worth seeking help from a GP or psychosexual therapist. Common causes: Relationship problems - such as becoming overly familiar with your partner, poor communication or trust issues

- such as becoming overly familiar with your partner, poor communication or trust issues Sexual problems - including erectile dysfunction or vaginal dryness

- including erectile dysfunction or vaginal dryness Stress, anxiety or depression

Age - sex hormones fall during the menopause. Low libido can also occur due to the side effects of medication or mobility problems

- sex hormones fall during the menopause. Low libido can also occur due to the side effects of medication or mobility problems Pregnancy and breastfeeding - can cause changes in hormone levels, exhaustion or altered priorities as people focus on their child

- can cause changes in hormone levels, exhaustion or altered priorities as people focus on their child Underlying health issues - such as heart disease, cancer and diabetes

- such as heart disease, cancer and diabetes Medication - including antidepressants and drugs for high blood pressure

- including antidepressants and drugs for high blood pressure Alcohol and drugs Source: NHS Choices Advertisement

Whereas men were most concerned about catching an infection and were slightly more likely to be anxious or dissatisfied.

The researchers, led by Dr Alison Parkes, wrote in their paper: 'Low desire has been identified as the most common female sexual problem across many studies.

'And [it] has been linked to relational factors including lower emotional closeness and difficulty communicating about sex.'

She added: 'We also noticed poor sexual health groups had certain characteristics in common.

'They were generally more likely to have started having sex before the age of 16 and to experience depression, alcohol or drug use.'

Twelve per cent of women said they didn't enjoy sex, compared with five per cent of men.

And women were three times as likely to report physical pain (seven per cent versus two per cent).

Both sexes were equally likely to have problems like erectile dysfunction or vaginal dryness.

But while men were seven times more likely to orgasm too soon, one in six women said they struggled to orgasm at all.

The study, because it was based entirely on surveys, could not explain why women appeared to have worse sexual experiences.

Researchers pointed to possible factors which could have damaging effects, such as hormone changes during menopause and a higher risk of being forced into sex by their partners.

A shocking one in 10 women in the study said someone had made them have sex against their will at some point during their life, compared to one in 100 men.