Whatever else aging does, it does not kill the sex drive.

Men and women continue to participate in sexual intercourse and masturbation well into their 70s and 80s, according to a study announced today.

Considered the first comprehensive national survey of sexuality among older adults in the United States, the research exposes what really goes on behind bedroom doors and drawn curtains, and it's probably more than you think.

The results, detailed in the Aug. 23 issue of the New England Journal of Medicine, are part of the University of Chicago's National Social Life, Health and Aging Project (NSHAP). The findings come from interviews and physical exams conducted between July 2005 and March 2006 of 3,005 U.S. adults ranging in age from 57 to 85 years old.

Ageless activities

Sexual activity declined slightly with age, the researchers found. Even so, more than half of 75- to 85-year-olds reported a roll in the hay at least two to three times a month, and 23 percent reported having sex at least once a week.

Oral sex is less "ageless." Nearly 60 percent of the participants under 65 years old said they had engaged in oral sex in the previous 12 months, compared with 31 percent for the over-75s.

Similar to findings for the younger-crowd, men were more likely than women to report sexual activity and masturbation. Fifty-two percent of men and 25 percent of women within an intimate relationship reported masturbating in the previous 12 months.

Sexual health

The level of sexual activity was closely tied with overall health, with individuals reporting "poor health" less likely to be sexually active. However, it could also be that those in poor health were not in the ideal condition to have sex, the researchers said.

Overall, approximately half of both men and women reported having at least one bothersome sexual problem, and nearly one-third reported at least two sexual issues.

"We found that older adults remain interested and engage in sex, yet many experience bothersome sexual problems that can compromise both health and relationships," said lead study author Stacy Tesser Lindau of the University of Chicago.

Among men, 37 percent reported having difficulty in achieving or maintaining an erection, with 90 percent indicating the issue was "bothersome." Erectile dysfunction topped men's trouble list, but other issues trailed not too far behind:

Lack of interest in sex: 28 percentClimaxing too quickly: 28 percentAnxiety about performance: 27 percentInability to climax: 20 percentAmong women, lack of interest in sex was the most prevalent sexual problem, among others:

Lack of interest in sex: 43 percentDifficulty with lubrication: 39 percentInability to climax: 34 percentFinding sex not pleasurable: 23 percentPain (most commonly vaginal pain during entry): 17 percentAmong all respondents in an intimate relationship who reported being sexually inactive for at least three months, the most common reason for no-sex was the male partner's physical health.

Sex in context

The bare-all results, the scientists say, are especially important in the elderly age group, which makes up the fastest growing segment of the U.S. population. Yet the "lack of reliable information about how sexual activity and function might change with age and illness, combined with taboos around discussing sex in later life, contributes to worry or even shame for many older adults," Lindau said.

She added that the survey results will allow older individuals to see their sexual experiences in context with others their age.

"It may comfort people to know that they are not alone in enjoying sexual activity as they age or in experiencing sexual problems, some of which could be alleviated with medical attention," Lindau said.

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