US researchers found 37 per cent of women had experienced a 'sleep orgasm' by the age of 45. Picture: Thys Dullaart

London - For nearly four in ten women, sleep isn’t just about recharging the batteries – it seems it’s also a source of great pleasure.

US researchers found 37 percent of women had experienced a “sleep orgasm” by the age of 45.

By contrast only half had enjoyed an orgasm during normal sex.

According to the study, so-called nocturnal orgasms can occur in females aged between the teenage years and the 50s, and whether they were single or married.

Meanwhile 83 percent of men participants had experienced the phenomenon, although mostly when in their teens.

The report by Indiana University’s Kinsey Institute for Research in Sex, Gender, and Reproduction, collected data based on interviews with 11 000 men and women about their sex lives.

It found 70 percent of women experience sexual dreams over their lifetime, and five percent had their first orgasm through dreaming at night. One woman claimed she has the experiences when she is going through a spell when she is not enjoying much activity in the bedroom department.

By comparison 100 percent of men had had sexual dreams, and 13 percent said their first orgasm occurred during sleep.

Dr Debby Herbenick, associate professor at Indiana University and a researcher at the Kinsey Institute, said that women’s orgasms are psychological.

Nearly half of women regularly had orgasms in their married sex life, but a tenth said they were yet to experience one.

Dr Herbenick added a number of factors often hold women back from having orgasms during sex, including an uncaring or selfish partner, lack of information about how to reach climax and concerns over body image.

Sleep orgasms tend to improve as women become older and more confident. Dr Herbenick said: “Orgasm generally gets easier with age and experience, and when women have sex with regular partners who they feel care about them. Thus we see higher rates of orgasm among those in their mid to late 20s, 30s, and 40s.”

Other experts said the key to achieving an orgasm while sleeping is in the mind. The Orgasm Answer Guide states: “There is good reason to believe that orgasms while sleeping are not, in fact, the result of stimulation, but instead are created in the brain.”

Daily Mail