Poor sleep may affect good sex in later life

"Good night's sleep boosts sex life for women over 50," reports the Mail Online.

US researchers asked more than 93,000 women aged 50 to 79 about their sleep patterns, difficulty sleeping, sexual activity and sexual satisfaction. They found women who sleep five or less hours a night, or who have insomnia, were less likely to have satisfying sex lives.

A higher proportion of women who reported they were satisfied were married or in an intimate relationship. However, women living without a partner who slept less than seven to eight hours were more likely to be sexually active but less likely to be sexually satisfied.

The research, part of an ongoing study of menopausal women in the US, took account of factors that could affect both sleep and sex, such as health problems, menopausal symptoms, age, and medicines use, including HRT. However, it only asked the questions at one point in time, so we don't know whether sleep problems happened before or after any sexual problems. This type of research can't tell us whether sleep is a cause of sexual problems.

Sleep is important for much of our wellbeing, however, including mental and physical health. It would not be surprising if lack of sleep also affected women's sex life.

Where did the story come from?

The study was carried out by researchers from a number of US institutions: the Mayo Clinic, Harvard Medical School, Ohio State University, Georgetown University, Wake Forest School of Medicine, Stony Brook University, Veteran Affairs Palo Alto Health Care System, University of Texas and the University of California. It was funded by the US National Institutes of Health. The study was published in the peer-reviewed journal Menopause.

The Mail Online gave a reasonable overview of the study, although it did suggest that lack of sleep had been established as a cause of poor sexual satisfaction, rather than simply linked to it.

The Daily Telegraph's report approached the research from the perspective of a woman's "frustrated lover", advising readers to "Listen to your partner when she says she's too tired for sex" and saying that the research shows tiredness may not just be a "thin alibi… to avoid amorous relations". Its coverage suggests that their readers would otherwise ignore women's protests that they didn't feel like sex, which one hopes is not the case.

What kind of research was this?

This is a big cross-sectional observational study. Cross-sectional studies can show how people feel at one point in time, and make links between factors (in this case sleep and sex). However, they cannot show that one factor causes another.

What did the research involve?

Researchers analysed information given by 93,668 women aged 50 to 79, who took part in the Women's Health Initiative Observational Study, carried out from 1994 to 1998. After adjusting their figures to take account of potential confounding factors such as illness and medicines, they looked to see if there was a link between how women said they slept, and their sexual activity and satisfaction.

Most of the measures included in the study were self-reported. To measure sleep over the past four weeks, women were asked:

• how many hours they slept at night
• whether they had one of a number of factors suggesting insomnia (trouble getting to sleep, waking repeatedly, trouble getting back to sleep, waking too early, unrefreshing sleep)
• whether they snored or fell asleep easily during quiet times in the day

To measure sexual function, they were asked:

• whether they'd had sexual activity with a partner during the past year
• how satisfied they were with their current sexual activity

Many women didn't answer the sexual questions (34% for sexual activity and 43% for sexual satisfaction), which could affect the reliability of the results.

The researchers took account of a wide range of possible confounding factors, including women's age, marital status, income, physical activity level, overall health, use of antidepressants, use of HRT, depression, weight and alcohol use.

What were the basic results?

Just over half (52%) of women who answered the question said they'd had sexual activity with a partner over the past year, and 57% said they were very or somewhat satisfied with their current sexual activities. About one third (31%) of women said they had symptoms of insomnia.

Women who slept for five or less hours a night, or who had insomnia, were less likely to feel satisfied with their sex lives than women who slept seven to eight hours and did not have insomnia:

• Women who slept five or less hours were 12% less likely to feel satisfied than women who slept seven to eight hours (odds ratio [OR] 0.88, 95% confidence interval [CI] 0.81 to 0.95).
• Women with insomnia were 8% less likely to feel satisfied than women without insomnia (OR 0.92, 95% CI 0.87 to 0.96).

Less sleep was linked to a 12% lower chance of having had sexual activity with a partner during the past year (OR 0.88, 95% CI 0.80 to 0.96). However, insomnia symptoms alone did not seem related to chances of having sex with a partner.

How did the researchers interpret the results?

The researchers said their results "suggest the potential importance of obtaining high-quality and sufficient sleep," for good sexual function.

They say future studies into sleep and sex in women after the menopause should be carried out over time, so that the changing relationship between sex and sleep can be clarified. 

Conclusion

These results show that women who sleep better are more satisfied with their sex lives, and more likely to be sexually active with a partner. However, the study can't tell us why this is. So many factors have the potential to affect both sleep and sexual satisfaction, that it's always going to be difficult to un-tangle the relationship between the two.

There are a few limitations to the study that make the results less reliable. Although it was a big study, a large proportion of the women chose not to answer the questions about sex. The questionnaire included the option to tick "prefer not to say". This means the results may not be representative of all the women in the study.

It's also important to note that the questions were asked only once, so we don't know how the relationship between sex and sleep changed over time. For example, it could be that some women's sexual satisfaction declined after they'd started having trouble sleeping, or that other women's satisfaction increased when their insomnia improved.

Conversely, women may have started having trouble with both sleep and sex after a life event such as bereavement, or because of a physical illness. A cross-sectional study can't help us unpick these possibilities. The study didn't ask about life events such as bereavement or divorce, although it did ask about whether women had a current sexual partner.

These caveats aside, it's well-known that sufficient sleep is important for health and general wellbeing. It would not be surprising if this extended to sexual wellbeing and satisfaction.

Find out more about how to get a good night's sleep.