Posted with permission from Medical Daily

A relationship changes when a couple moves in together. Some changes are good (i.e., cooking dinner together) while some of them aren’t so great for one or the other partner (i.e., toilet seat up). Now, there’s a new factor to consider: A team of researchers at the University of Southampton in the U.K. suggests living together and relationship duration can influence sexual desire in couples.

The study, published in the British Medical Journal Open, found both men and women lose interest in sex with time. For both sexes, poor physical and mental health, poor communication and a lack of emotional connection during sex can cause sexual desire to dwindle. Interestingly, women were twice as likely as men to lose interest in sex when living with their partner or while in a relationship lasting more than a year.

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This finding confirms what most people already know: Women are more likely to lose interest in sex over time than men, but cohabitation and relationship duration are strong predictors of sexual desire among women. Similarly, a 2012 study in the Journal of Sex & Marital Therapy found the length of a relationship influenced a woman’s sex drive more than sexual satisfaction and satisfaction with the relationship. The researchers theorize this decrease occurs because, over time, the relationship moves from passionate love to compassionate love.

In the new study, the U.K. researchers noted that many of the women’s sexual turnoffs were linked to having children under 5 years old, and to giving birth in the last year.

“This may be due to fatigue associated with a primary caring role, the fact that daily stress appears to affect sexual functioning in women more than men or possibly a shift in focus of attention attendant on bringing up small children,” the authors wrote in the study.

This coincides with previous research that suggests sex drive decreases after pregnancy. In a study featured in the book Sexuality During and After Pregnancy, author E.L. Ryding found 20 percent of postpartum women had little interest in sex three months after pregnancy, and another 21 percent experienced a complete loss of sexual desire and sometimes an aversion to any kind of sexual activity. Women’s sex drives compete with the overwhelming fatigue of taking care of a newborn, so when a new mother gets a break from this physical attachment, sex could rank low in the list of priorities.

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The researchers found that among those surveyed—4,839 British men and 6,669 women aged 16 to 74—34 percent of the women surveyed reported a loss of interest in sex, compared to just 15 percent of men. For women, the lack of interest in sex was most common between the ages of 55 and 64, whereas for men it was between 35 and 44. Moreover, two in five older women were unsatisfied with their sex lives, which researchers believe is linked to stress, pressures of family life and work.

“Our findings show us the importance of the relational context in understanding low sexual interest in both men and women. For women in particular, the quality and length of relationship and communication with their partners are important in their experience of sexual interest,” Cynthia Graham, lead author of the study and a professor at the  Centre for Sexual Health Research at the University of Southampton, said in a statement.

Graham also explained that the study highlights the need to assess and, if necessary, treat sexual interest problems in relationships in a holistic, gender-specific way that goes beyond drugs. The U.S. Food and Drug Administration recently approved flibanserin, the first ever drug treatment for hypoactive sexual disorder in premenopausal women to boost the female libido. However, if the problem is more about open communication and emotional closeness, talking to your partner may help more than taking a drug.