Introduction

Loss of libido is the most common sexual complaint of women, often being a final common pathway of many sexual disorders. Estimates range from 30–45% depending on the population sampled, increasing in the postmenopausal age group [1]. However, the degree of distress associated with loss of libido may be minimal and therefore not sexually dysfunctional. Lack of arousal and orgasmic disorders are frequently correlated with loss of libido, as are sexual pain disorders. It is important for the medical doctor to help the patient decipher the chain of events and their combination, to facilitate change and improvement. Making assumptions about a particular set of expectations is likely to lead to neglect of key factors. In psychosexual medicine, listening and observing the patient’s expression of feelings can help to interprete the predominant issue(s) which can be resolved using brief psychotherapeutic intervention.

The menopause

Studies of the menopause and sexual relationships have reported a reduction in sexual activity with age. However, a US study of 18–59-year-old adults has reported sexual difficulties in 43% of women and 31% of men [2]. An Australian longitudinal study, observing women from the age of 45 to 55 suggested that female sexual dysfunction increased from 42% to 88% from the early-to-late menopause [3]. However if “distress” is included in the definition of female sexual dysfunction, this is reduced significantly [4]. There is a small variation amongst European women, country by country, which indicates that the frequency of intercourse varies, but body mass index (BMI) is the only significantly varying factor.

There are increasing sexual difficulties with age: in women these may be correlated with estrogen levels, but not androgens, although testosterone levels have not consistently been shown to reflect sexual functioning in younger women either. Predictably women who have a sexual partner are more likely to be sexually active and to have increased satisfaction within their relationship. Cessation of sexual activity is more likely to be male partner driven within a relationship. A recent lifestyle survey from the UK, published in 2013 indicated that sexual inactivity was more common with reducing health status in both men and women, and therefore with age. One in six people reported a health condition that affected their sex life in the previous year: 24% of men and 18% of women had sought help or advice from a health-care professional. Men report an increase in ejaculation and satisfaction problems, but less erectile dysfunction, although the wide availability of phosphodiesterase inhibitors may have changed the distribution of sexual problems in men. In women, sexual satisfaction rates have been increasing overall and have been linked with earlier sexual debut and more positive attitudes to female sexuality [5]. There is a greater expectation in women to continue to be sexually active and satisfied, but this is not universal. Individual preconceptions regarding aging and behavior vary hugely.

Various studies have been contradictory with respect to menopause and the cause of sexual difficulties being age-or hormone-related. Overall when dealing with individual patients, the patient will be the “expert” in her condition and the clinician needs to help her unravel the issues around cause and effect.

Sexual disorders

The Diagnostic and Statistical Manual of Mental Disorders (DSM) V classification now combines desire and arousal disorders as they are almost invariably linked. Isolated genital arousal disorder may however exist in postmenopausal women due to the physical changes of the menopause causing vulvo-vaginal atrophy. Over time this condition is commonly associated with reduced desire. Development of desire disorder may be protective from distress and dissatisfaction when preceded by dyspareunia or adverse changes in sexual responsivity.

Orgasmic disorders are a separate category, which may include a lack of or reduction in quality of sex, sometimes due to direct hormonal deficiencies or a culmination of other sexual issues. Dyspareunia and vaginismus are now also classified together, but are separate from non-coital pain disorders, which can also cause severe sexual dysfunction, for example vulvodynia and bladder pain syndrome.

The duration of the problem is an important factor in diagnosis of female sexual dysfunction. Short-term issues may be normal and a manifestation of the effects of life circumstances. Sexual difficulties may also reflect the overall psychological well-being of the individual. Of importance in the menopausal woman, are the organic causes of sexual problems that may impact on psychological health. The etiological routes of anatomic, hormonal, neurologic, vascular and other abnormalities affects sexual self-esteem and functioning, given that sex is a mind and body activity.

Sexual response cycle

Although the Masters and Johnson model of human sexuality [6] has been useful in explaining the sequence of phases in the human sexual response cycle, the Basson model of female sexuality [7] facilitates a clearer understanding of the drivers and difficulties specifically involved in the female sexual response cycle. A spontaneous drive to be sexually active may be less significant in a longstanding relationship than the need for emotional and physical satisfaction and emotional and physical intimacy. A sexually neutral woman is able to be receptive to sexual stimuli in the right circumstances, and desire and arousal may occur concomitantly, rather than desire being a driver for activity. A better understanding of her emotional and relationship issues can be crucial to understanding the physical responses of a woman, particularly with the major life changes occurring at the menopause. How she perceives the changes happening to her, including her role in society, at work and within her family, all reflect her self-esteem and sexual confidence.

Hormonal impact

Estrogen deficiency has a significant impact on sexual function, including changes in urogenital anatomy, nerve transmission, blood flow, sleep disorders, mood alterations and vasomotor symptoms. Within the genital tract, shortening and loss of elasticity in the vagina occurs and along with reduced secretions and thinning of the vaginal epithelial layers, increases the risk of trauma and discomfort, particularly in association with sexual activity. Atrophy of the tissues causes pain, dryness, lack of arousal, reduction in desire, reduced orgasm and sensitivity, and increasing urinary symptoms. An alteration in vaginal pH can cause recurrent infections such as bacterial vaginosis and thrush. More covert symptoms of lack of desire and arousal, decreased orgasmic potential and postcoital bleeding causing anxiety, can all lead to avoidance of sex, deterioration in a relationship and an acceptance of sexual decline. If not recognized, this becomes a repetitive cycle that is difficult to unravel or arrest. Psychologically, behavioral patterns become embedded and their initial trigger becomes less identifiable. At this point, recovery and re-engagement with a sexual partner can be troublesome.