shows the distribution of Natsal-SF scores for the 4913 men and 6777 women who were sexually active in the past year and completed the Natsal-SF. Scores ranged from −2·992 to 2·163 in men and −2·914 to 2·325 in women. The black dashed line marks the lowest quintile, used as the cutoff to denote low sexual function.
Distribution of raw latent scores according to the Natsal-SF in sexually active men and women
We explored associations between low sexual function and sociodemographic, health, relationship, and sexual behaviour variables (). The percentage with low sexual function increased with age in sexually active men () and women (). However, the strength of the association did not increase beyond the 55–64-year-old age group.
Factors associated with low sexual function (lowest quintile of gender-specific distribution) in sexually active men
Factors associated with low sexual function (lowest quintile of gender-specific distribution) in sexually active women
After adjustment for age, low sexual function was associated with unemployment, but not with living in an area of higher deprivation (). We noted strong associations between low sexual function and current depression and with poor self-assessed general health (). Among women, we saw an association with menopausal status and low sexual function, but women who were pregnant in the past year were less likely to have low sexual function than were women who had not been pregnant ().
Compared with individuals who were cohabiting, individuals who had never lived with a partner were more likely to have low sexual function, as were those who had been in a relationship that had ended (). Participants who were not happy with their relationship were more likely to have low sexual function, as were both sexes who did not find it easy to talk about sex with a partner ().
Low sexual function was associated with lack of sexual competence (defined as absence of duress and regret about timing, autonomy of decision, and use of a reliable form of contraception) at first intercourse25
and with sexual experience in the past 4 weeks (specifically, having sex fewer than four times, masturbation, and no genital contact without intercourse; ). We also noted an association between low sexual function and having a same-sex partner in the past 5 years (). For men, we noted a strong association between low sexual function and paying for sex in the past year (). Among women only, we noted a strong association with reporting higher numbers of lifetime partners (). Low sexual function was also associated with negative sexual health outcomes; most strongly with non-volitional sex but also with diagnosis with a sexually transmitted infection in the past 5 years ().
We also report on the proportion of sexually active men and women endorsing items in the first two components of the Natsal-SF, which focus on sexual response problems and the sexual relationship. For component three, appraisal of sex life, we compare reports of sexually active and inactive participants ().
Self-appraisal of sex life by sex, age group, and whether sexually active, in individuals who reported ever having sex
shows the proportion of men and women reporting specific problems with sexual response lasting at least 3 months in the past year. For men, the most commonly reported problems were lack of interest in sex (14·9%), reaching a climax more quickly than desired (14·9%), and difficulty getting or keeping an erection (12·9%). For women, the most common problems were lack of interest in sex (34·2%), difficulty in reaching climax (16·3%), an uncomfortably dry vagina (13·0%), and lack of enjoyment (12·1%). Reporting lack of interest was twice as common among women compared with men. Reporting lack of enjoyment, physical pain and difficulty reaching climax were also more common among women (). In the youngest participants (aged 16–24 years) the most common problem among men was reaching a climax too quickly (16·5%); in women it was lacking interest in sex (24·8%) and difficulty reaching climax (21·0%).
Percentage of sexually active participants reporting problems with individual sexual response lasting 3 months or more in the past year, by sex and age group
Reporting at least one sexual function problem lasting 3 months or more in the past year was common (41·6% of men and 51·2% of women). Although the proportion of sexually active men and women reporting one or more problem increased steadily with age, this finding was largely due to the age-related increase in erectile difficulties in men (from 7·6% of men aged 16–24 years to 30·0% of men aged 65–74 years) and vaginal dryness in women (from 9·4% to 20·0% across the same age range). We identified two problems that declined with age: reaching a climax too quickly in men (from 16·5% to 10·8%) and anxiety during sex among women (from 8·2% to 2·0%).
Items relating to sexual function within relationships were asked of individuals who were sexually active and in a relationship lasting at least a year before the interview. The most common issue within relationships was an imbalance in level of interest in sex between partners (; exact figures shown in appendix p 1
). We noted small differences between the sexes, with women slightly more likely to report an imbalance in interest (23·4% of men vs
27·4% of women, p=0·0010) and not very often or hardly ever feeling emotionally close to their partner (1·3% vs
2·6%, p=0·0017), and men being slightly more likely to report not sharing the same sexual likes and dislikes (9·9% vs
Percentage of participants with particular attitudes towards their sexual partnership, by sex and age group among those who were sexually active and in a sexual relationship lasting the whole year
Finally, 18·0% of men and 17·1% of women said their partner had had sexual difficulties in the past year. The proportion increased with age, but more so for women than men such that this was reported by almost twice the proportion of women (43·3%) as men (23·1%) in the oldest age group (65–74 years).
shows self-appraisal of sex life in terms of dissatisfaction, distress or worry, avoidance of sex because of own or partner's sexual difficulties, and seeking help or advice among ever-sexually active participants (exact figures shown in appendix p 2
The proportion of participants expressing dissatisfaction with their sex life was substantially higher in individuals who did not report sex in the past year (sexually inactive) compared with those who did (sexually active): 31·8% for sexually inactive men versus 14·9% for sexually active men and 22·4% for sexually inactive women versus 11·7% for sexually active women. Dissatisfaction varied with age in sexually inactive men and women and sexually active women, but not among sexually active men.
Distress or worry about an individual's sex life was less commonly reported than was dissatisfaction. Distress differed little between sexually active (9·9%) and inactive men (15·4%), and not at all between sexually active (10·9%) and inactive (9·5%) women. For sexually active individuals, the proportion of men reporting distress increased by age, but there was no variation by age for women. In sexually inactive women, the proportion reporting distress declined by age, from 13·4% of those aged 16–24 years to 6·7% of those aged 65–74 years (p=0·0011). In sexually inactive men, the proportion reporting distress declined from 26·2% of those aged 35–44 years to 8·6% of those aged 65–74 years (p=0·0104 for differences across entire age range).
Avoidance of sex because of sexual difficulties was more common in sexually inactive individuals than sexually active individuals (21·4% vs 11·0% for men; 17·4% vs 13·4% for women). In all groups, avoidance of sex was increasingly common with age, apart from in sexually inactive women, for whom it declined from 23·3% in individuals aged 45–54 years to 13·6% in those aged 65–74 years.
Overall, reported sexual dissatisfaction and avoidance of sex was greatest in individuals who did not report sex in the past year (compared with those who did), but most sexually inactive individuals reported that they were not dissatisfied, distressed, or avoiding sex because of sexual difficulties.
Seeking help or advice for sex lives from any source in the preceding year was more common in sexually active women (16·6%) than in sexually inactive women (7·4%), but this tendency did not differ by sexual activity status in men (14·4% for sexually active vs 13·1% for sexually inactive). Irrespective of sexual activity status, help-seeking was more common in younger participants than older ones; with the sources of help in those aged 16–24 years being predominantly informal (data not shown).