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Sex difference in libido

Younis, Ihab; Abdel-Rahman, Sherine H.

doi: 10.1097/01.XHA.0000432482.01760.b0
Review article
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A sex difference in libido does exist. Men report desiring sex more frequently, with more partners, and with more variety compared with women. Sex differences in masturbation are large and consistent. Women and girls are less likely to masturbate than men and boys, and some evidence indicates that male individuals who masturbate do it more frequently than female individuals. Most studies on extramarital sexual activity have found that men report more partners than women. In both heterosexual and homosexual relationships, men have more frequent and more varied fantasies than women, and men report thinking about sex more often than women. Living without sexual gratification is easier for women than for men. Although sexual desire declines with age for both sexes, most men retained at least occasional sexual desire, whereas the great majority of women articulated no sexual desire. In the authors’ view, the mentioned issues may explain the imposition of Hijab on women and the allowance of polygamy for men.

Department of Dermatology and Andrology, Banha University, Banha, Egypt

Correspondence to Ihab Younis, MD, 6 Syria St., Mohandeseen, 12411 Giza, Egypt Tel: +233377576; e-mail: ihabyounis@hotmail.com

Received August 27, 2013

Accepted September 11, 2013

Walking on the streets of Cairo wearing hot shorts will definitely have different impacts according to the sex of the wearer! Indeed, research has indicated that a sex difference in libido does exist.

Libido is a comprehensive and yet elusive word that defines basic human mental states – and their biological counterparts – involved in the beginning of sexual behavior. It has three main roots: biological, motivational–affective, and cognitive 1.

In this review two aspects of sex difference in libido will be considered, namely, quantitative and qualitative aspects. These aspects mainly follow the categories suggested by Baumeister et al. 2.

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Quantitative aspects

Desired frequency of sex

The findings from many studies suggest that men want sex more frequently compared with women. Ard 3 found that, in couples who had been married for over 20 years, husbands continued to prefer intercourse more often compared with wives. Likewise, Brown and Auerbach 4 reported that a majority of husbands (60%) but only a minority of wives (32%) said that they would prefer to have sex more often. In a sample of couples aged between 51 and 61 years, Johannes and Avis 5 found that women were more likely than men to wish for less frequent sex than they were having, whereas men were more likely to wish for more frequent sex than they were having.

Among 20-year-olds who had been dating for about 2 years, no mean sex difference was found in self-reported sexual desire. This suggests that there may be a phase of equal desire 6.

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Sex differences in masturbation

Sex differences in masturbation are large and consistent. Even past the age of 60, men masturbate more than women 7.

For example, in a survey of German teenagers aged between 16 and 17 years, it was found that 80% of the boys, but only 25% of the girls, engaged in masturbation during the past year, and boys averaged five times per month as opposed to once per month among the girls 8.

Arafat and Cotton 9 found that women and girls were almost four times more likely than men and boys to say that they had never masturbated (39 vs. 11%). The most common reason for not masturbating was a lack of desire, and this was reported by more of the nonmasturbating female individuals (76%) than the nonmasturbating male individuals (56%).

Jones and Barlow 10 found that 45% of men but only 15% of women reported masturbating at least once per week. Meanwhile, nearly half the women in their sample (47%) but only 16% of the men said that they had never masturbated.

Indeed, in a meta-analysis of sex differences in sexual behavior, Oliver and Hyde 11 found that masturbation showed the largest difference among all the variables they examined, with men nearly a full standard deviation higher than women.

Although masturbation is a violation of the most sacred vows of chastity for Catholic priests, yet apparently most priests do engage in masturbation. Sipe 12, after extensive interviews with many priests, reported that not only do priests masturbate, but they masturbate more than nuns.

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Desired number of sex partners

Men desire significantly more sex partners than do women. On being asked the question ‘How many sex partners would you like to have over the next 2 years of your life?’, men reported wanting about eight partners, whereas women wanted approximately one. Over the course of a lifetime, men wanted around 18, whereas women desired four or five 13.

Miller and Fishkin 14 asked a sample of college students how many sex partners they would like to have over the rest of their lives if they were not constrained by any factors such as disease or laws. The mean response by women was 2.7 sex partners, whereas that by men was 64.

Desire for multiple partners can lead to extramarital or extradyadic involvement. Most studies on extramarital activity have found that men have more partners than women, in both heterosexual and homosexual relationships. For example, Spanier and Margolis 15 found that 26% of unfaithful husbands had had more than three extramarital partners, as compared with only 5% of unfaithful wives. Conversely, wives outnumbered husbands in the category of having only one extramarital partner (64 vs. 43%). The same conclusion emerges from studies on lesser infidelities, such as necking or petting with someone other than a steady dating partner: men were found to do this more than women 16.

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Sexual thoughts, fantasies, and spontaneous arousal

Sexual fantasies are also a good indicator of sexual desire because they are explicitly sexual and require conscious attention but are not constrained by opportunities, social pressures, or other external factors. Sex differences in sexual fantasyhave been examined in many studies, which have generally concluded that men have more frequent and more varied fantasies compared with women – that is, men fantasize more often than women, have a wider variety of partners compared with women, and engage in a wider variety of sexual acts compared with women 2.

Vanwesenbeeck et al.17 developed a sexual compulsion scale with items such as ‘I think about sex more than I would like’ and ‘I must fight to keep my sexual thoughts and behavior under control’. Men scored higher than women on this scale, indicating a greater sense of being sexually driven.

Men and women were exposed to explicit erotic films and were asked to fantasize about their real-life partner versus someone else. Among women, the instruction to fantasize about their partner resulted in stronger subjective sexual arousal to the explicit film compared with the instruction to fantasize about someone else. This suggests that response to erotic stimuli is affected by the viewer’s interpretation of the depicted relationship 18.

Thus, as compared with women, men think about sex more often, report more frequent arousal, and have more frequent and variable fantasies. These findings would be most consistent with the view that men have a higher sex drive 19.

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Sex differences in willingness to forego sex

A woman might enjoy a full and active sex life for a period, then lose her partner and have no sexual activity at all for some time, and then resume active sex with a new partner. Such discontinuities are almost never found among men 20.

In-depth history taking has indicated that many women seem to adapt easily to a complete absence of sexual activity over long periods of involuntary abstinence, unlike men. The fact that women were more willing than men to do without sexual activity altogether supports the view that women are less strongly motivated to find some sexual gratification consistently across time. When men lose one source of sexual gratification, such as on breaking up with a regular sex partner, they apparently seek out a new one soon or at least step up the frequency of masturbation 21.

Clerical celibacy among both sexes was studied by Murphy 22 using a questionnaire survey and a sample of several hundred. Her results suggest significantly greater success at celibacy among female than among male Catholic clergy. More male clergy (62%) than female clergy (49%) reported having been sexually active since they took their vows of celibacy. Among the sexually active, the men had had more partners than the women; 24% of the sexually active men, whereas only 3% of the sexually active women reported having had more than five partners since taking their vows. The men were more likely than the women to emphasize the orgasm as the most important part of the experience (20 vs. 2%). The women were more likely than the men to terminate the sexual relationship (i.e. women might just lapse once or briefly, whereas many men would continue violating their vows).

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Sex differences in prevalence of low sexual desire

Therapy studies have confirmed that lack of libido is more common among women than among men. Hawton and Catalan 23 studied 154 patients presenting for sex therapy. The problem of ‘impaired sexual interest’ was the most common problem (58%) among female patients but the least common problem (4%) among male patients.

In a study of over 900 patients who were being treated for a variety of sexual dysfunctions, women appeared to be four times more vulnerable than men to the problem of low sexual desire 24.

In addition, Ventegodt25 concluded that among women in Denmark, one of the most frequently reported sexual problems was decreased sexual desire (11% of women vs. 3% of men).

In the UK National Survey of Sexual Attitudes and Lifestyles, 11 161 men and women were studied between 1999 and 2001 (age range 16–44 years). Interestingly, responses varied widely according to the time frame given. A total of 17% of the men reported a lack of sexual interest for 1 month in the previous year compared with 40.6% of the women. When asked about problems that lasted for 6 months in the previous year, only 1.8% of the men and 10.2% of the women reported having a lack of interest in sex 26.

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Sexual activity according to sex and age groups

Although many elderly men and women engage in sexual activities, sexual desire typically decreases with age. The results obtained by DeLamater and Sill 27 indicate that age is significantly associated with desire, if the effect of other variables studied is excluded. The relationship is stronger among men than among women. However, sexual desire does not decrease as fast as popular belief dictates. It is not until the age of 75 years or older that the majority of women and almost a majority of men report a low level of sexual desire. These results are consistent with previous findings 28,29.

Although sexual desire declines with age for both sexes, women seem to be affected earlier. In men, the lack of sexual desire emerged a decade later and did not increase as much compared with women. At an age of over 70 years, most men retained at least occasional sexual desire, whereas the great majority of women articulated no sexual desire. Similar effects were found for the intensity of sexual desire. For both sexes, the presence of a partner was a major determinant of sexual activity with advancing age: men who lived with a partner were sexually active well into their 60s (>80%) and 70s (>50%). A different picture emerged for those men without partners: only a minority of men without partners were reportedly sexually active in their 60s, and hardly any in their 70s. Most women who lived with a partner were sexually active at 61–70 years and about a third above 70 years. A few women without partners were sexually active at 61–70 years and hardly any above 70 years 30.

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Qualitative aspects

Sex difference in watching pornographic material

A Norwegian study 31 reported that 94% of men and 68% of women were exposed to pornography. As regards the use of pornography when masturbating, the estimated mean percent was 42% among heterosexual men versus 12% among heterosexual women.

The use of pornographic material among adolescents in Hong Kong was over 70% 32. Compared with female individuals, male individuals were almost three times more likely to be exposed to pornographic material, regardless of the type of pornographic material.

Men show a preference for pictures depicting other men receiving oral sex and in a dominant intercourse position and vice versa for women, as both sexes have a tendency to imagine themselves in the pornographic scenario 33. In addition, men have more interest in close-up images of the genitals than do women because of decreased interest in contextual information 34.

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Sex differences in the content of sexual fantasy

A qualitative analysis of the sexual fantasies of men and women suggested that men’s fantasies contained more visual imagery and explicit anatomic detail, whereas women’s sexual fantasies contained greater reference to affection, emotions, and story line 35.

This result has subsequently been confirmed in a more empirical manner by other investigators. Mednick 36 asked 48 male and 48 female graduate and undergraduate students to describe, in a narrative form, their most common fantasy over the previous 3 months. When these written fantasies were later examined, it was found that the women were more likely than the men to imagine themselves as the recipients or the objects of sexual activity rather than the providers or performers; the opposite was true for the men.

Gil 37, in a sample of conservative Christian men and women, found that romantic themes were mentioned twice as often in the sexual fantasies of women than in those of men; among men, there was greater mention of explicit scenes.

When a sample of 307 college students were asked about the importance of emotional setting (e.g. mood and ambience) and physical setting (e.g. looks, textures, and sounds and smells of a place) in their sexual fantasies, women were reported to find these factors more important compared with men. Similarly, women, more often than men, reported that the build-up that precedes the sexual encounter was an important part of their sexual fantasies 19.

The fantasy of having sex with multiple partners of the opposite sex can be exciting to both men and women, in part because it signifies one’s sexual desirability and power. Nevertheless, fantasizing about having sex with multiple partners at the same time appears to be more consonant with the male stereotype of being a ‘superstud’ than with the female stereotype of wanting a close, loving, monogamous relationship. It is not surprising, therefore, that a number of studies have shown that men are more likely than women to have this fantasy. For example, Wilson 38, in a survey of 4767 adults, found that 31% of the men and 15% of the women reported a fantasy involving group sex. Similar sex differences were reported by other workers: Hessellund 39 reported figures of 37 and 7% for men and women, respectively; Sue 40, 19 and 14%; and Davidson 41 42 and 17%.

Chivers et al. 42 exposed heterosexual men and women to audio narratives describing sexual or neutral encounters with female and male strangers, friends, or long-term relationship partners. Among women, but not among men, arousal to both female and male friends was significantly lower than to the stranger and long-term relationship partner. These results suggest that the relationship context may be a more important factor in a heterosexual women’s physiological sexual response than sex cues.

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Sex differences in neural response to sexual stimuli

Functional MRI of men and women viewing sexually arousing stimuli shows that the amygdala and hypothalamus are more strongly activated in men than in women when viewing identical sexual stimuli. This was true even when women reported greater arousal. Sex differences were specific to the sexual nature of the stimuli, were restricted primarily to the limbic region, and were larger in the left amygdala than in the right amygdala. Men and women showed similar activation patterns across multiple brain regions, including ventral striatal regions involved in reward. These findings indicate that the amygdala mediates sex differences in responsiveness to appetitive and biologically salient stimuli; the human amygdala may also mediate the reportedly greater role of visual stimuli in male sexual behavior 43.

It is important to distinguish whether the sex differences observed in neural activation reflect differences in cognitive processing between men and women in response to sexual stimuli or simply differences due to inherent morphological or physiological sex differences. For example, the increased hypothalamic activation observed in men could be because of the fact that men can have erections, which alter hypothalamic activity 44.

An investigation of the EEG response to same and opposite sex stimuli in men and women supports imaging findings and suggests that women distinguish less between same and opposite sex stimuli than do men 45.

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The opposite side of the story

The field of sexuality has long focused on studies on sexual response and behavior of men and has established men’s sexuality as the norm 46. This may imply thatassessing female sexuality as a counterpart of male sexuality is imprecise.

Conley et al.47 reconsidered whether women desire (and have) fewer sexual partners compared with men, concluding that such sex differences are artifacts of ‘inappropriate statistics and social desirability’ rather than reflections of underlying psychological differences.

Schmitt et al.48 criticized the theory of Conley et al.47 by saying that their work was based on a study that used inappropriate statistics to strongly refute sex differences in desired numbers of short-term sex partners, despite ample confirmatory evidence that sex differences exist in these short-term mating desires.

Savin-Williams and Ream 49 noticed that these sex differences may be due to sex differences in the expression of sexual desire. Women’s sexual desire may be more complex than men’s, focusing on contextual factors and emotional arousal, rather than the genitals. For example, women are more likely to report sexual arousal in response to verbal exchanges and nongenital touching than men. Another example of the complexity of women’s sexual desire is the greater flexibility in sexual orientation among women. Women are more likely than men to report that they are attracted to an individual regardless of sex. Therefore, women report bisexualitymore often than men and are more likely than men to report a change in their sexual identity across their lifespan.

Leiblum 50 indicated that a nearly universal stereotype holds that men are driven by their sexual impulses or drives, whereas women rarely feel desire. She reviewed the effect of menstruation, gestation, and lactation on female sexual desire, as well as the influence of estrogens and androgens. The suggestion she made was that, although differences in sexual drive and its behavioral expressions certainly exist, these sex differences may be narrowing as women gain political, social, economic, and reproductive freedom. Finally, it will be argued that these differences may be precisely what makes sex interesting and meaningful rather than the simple release of biological tension.

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Theoretical perspectives explaining differences

Biological and sociocultural factors may play a role in explaining the sex difference in libido. Among biological factors, testosterone is the most commonly studied hormone involved in sexuality. It plays a key role in sexual arousal in males, with strong effects on central arousal mechanisms 51. The connection between testosterone and sexual arousal is more complex in females 52. Women who participate in polyandrous relationships have higher levels of testosterone. However, it is unclear whether higher levels of testosterone cause increased arousal and in turn multiple partners or whether sexual activity with multiple partners causes the increase in testosterone 53. Although testosterone may play a role in the sexuality of some women, its effects can be obscured by the coexistence of psychological or affective factors in others 51.

On average, in adult human males, the plasma concentration of testosterone is about seven to eight times higher than that in the plasma of adult human females 54. This may explain some of the sex differences mentioned above.

Sociocultural factors may also have a role. Baumeister 55 offers a conceptualization of the relative contributions of nature and culture to human sexual desire. The point of departure is that there is no single correct answer that holds true for all human beings. Instead, he suggests that female sexuality, as compared with male sexuality, is more subject to the influence of cultural and social factors. Although male sexuality must frequently make concessions to opportunity and other external constraints, male desire is depicted here as relatively constant and unchanging, which suggests a powerful role of relatively rigid, innate determinants. Female sexuality, in contrast, is depicted as fairly malleable and mutable: it is responsive to culture, learning, and social circumstances. The plasticity of the female sex drive offers greater capacity to adapt to changing external circumstances, as well as an opportunity for culture to exert a controlling influence.

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Conclusion

The literature review aiming to answer the question ‘Is there a sex difference in libido?’ indicates that men experience more frequent and probably more intense sexual desire. This applies to both quantitative and qualitative aspects of libido. Biological and sociocultural factors may be responsible, at least in part, for this difference. From a personal point of view, the authors think that this difference may explain why women were asked to were ‘Hijab’ and why men were allowed to marry more than one woman.

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Acknowledgements

Conflicts of interest

There are no conflicts of interest.

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Keywords:

female sexuality; FSD; libido; obesity

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