Female sexual dysfunction

What is female sexual dysfunction?

Female sexual dysfunction (FSD) is a subjective dissatisfaction, leading to significant distress, with the level or nature of sexual activity.

Sexual dysfunction in women is a common problem and can significantly affect relationships and quality of life. The problem is often multifactorial. Biological, psychological, sociocultural, and relationship factors may all play a role, and ageing is a significant contributing factor. The risk factors are similar to those for erectile dysfunction in men, and the condition may be a marker for CVD or endocrine disease.

Definitions of female sexual dysfunction^{1 2 3}

Female sexual dysfunction refers to difficulties during the sexual response cycle that prevent a woman from experiencing satisfaction from sexual activity. Low or absent sexual desire is the most common sexual dysfunction in women, and its prevalence peaks during midlife.

The International Classification of Diseases (ICD) 11th Revision defines sexual dysfunction as follows:⁴

• Sexual dysfunctions are syndromes that comprise the various ways in which adults may have difficulty experiencing personally satisfying, non-coercive sexual activities. Sexual response is a complex interaction of psychological, interpersonal, social, cultural and physiological processes and one or more of these factors may affect any stage of the sexual response. In order to be considered a sexual dysfunction, the dysfunction must:

  • Occur frequently, although it may be absent on some occasions.

  • Be present for at least several months.

  • Be associated with clinically significant distress.

• Hypoactive sexual desire dysfunction is characterised by absence or marked reduction in desire or motivation to engage in sexual activity as manifested by any of the following:

  • Reduced or absent spontaneous desire (sexual thoughts or fantasies).

  • Reduced or absent responsive desire to erotic cues and stimulation.

  • Inability to sustain desire or interest in sexual activity once initiated.

• The pattern of diminished or absent spontaneous or responsive desire or inability to sustain desire or interest in sexual activity has occurred episodically or persistently over a period at least several months, and is associated with clinically significant distress.

• Sexual arousal dysfunctions include difficulties with the physiological or the subjective aspects of sexual arousal.

• Orgasmic dysfunctions refer to difficulties related to the subjective experience of orgasm.

The Diagnosis and Statistical Manual of Mental Disorders fifth edition (DSM-5) classifies FSD into three clinically significant types.⁵ For each diagnosis the disorder is experienced at least 75% of the time for at least six months (except for medication-induced FSD), resulting in significant distress. FSD can be lifelong or acquired, and generalised or situational. Exclusion criteria include nonsexual mental disorder, severe relationship distress (eg, partner violence) and other significant stressors. The three types, some or all of which may be present, are:

• Sexual interest/arousal disorder. This is defined as reduced or absent sexual interest, responsiveness, erotic thoughts and sexual pleasure.

• Female orgasmic disorder (absence, infrequency, reduction, delay of orgasm):

  • Lifelong anorgasmia may suggest unfamiliarity or discomfort with self-stimulation or sexual communication with her partner.

  • Delayed or less intense orgasms may be a natural process of ageing, due to decreased genital blood flow, atrophy and reduction in sensitivity.

• Genito-pelvic pain/penetration disorder (difficulty in vaginal penetration, marked vulvovaginal or pelvic pain during penetration, fear or anxiety about pain in anticipation of, during, or after penetration, and tightening or tensing of pelvic floor muscles during attempted penetration):

  • Genito-pelvic pain/penetration disorder includes fear or anxiety, marked tightening or tensing of the abdominal and pelvic muscles, or actual pain associated with attempts toward vaginal penetration that is persistent or recurrent for at least six months.

How common is female sexual dysfunction? (Epidemiology)

Sexual function is closely correlated with overall well-being and relationship satisfaction. Most women continue to consider sexual function important as they age. However, 45% of midlife women have sexual problems, and 15% have a sexual problem that causes significant personal distress. Female sexual dysfunction remains under-recognised and undertreated.⁶

Causes of female sexual dysfunction

Female sexual function involves hormonal, neurological, vascular, psychological and emotional aspects. Dysfunction may be triggered or maintained by any of these, or by the interplay between them. Female sexual function is also highly dependent on physical and psychological feedback, so that physical, emotional and psychological factors will affect one another, so that an original issue becomes clouded by others.

Sexual dysfunction is highly prevalent in older women. Many women experience a change in their sexual function during the years immediately before and after menopause. Common complaints include a loss of desire, diminished responsiveness and low sexual arousal. Evaluation is difficult because the dysfunction is usually multifactorial, but recently a cultural shift has led to increased expectation of a satisfactory sex life in older age.^{7 6}

Hormonal factors⁸

Hormones, particularly androgens and oestrogens, are involved in the sexual response, particularly in terms of the integrity and sensitivity of genital tissues.

Sexual function worsens with advancing menopause status. The most frequently reported symptoms include low sexual desire (40-55%), poor lubrication (25-30%) and dyspareunia (12-45%), one of the complications of genitourinary syndrome of menopause (GSM).⁹

Endocrine conditions^{10 11 12}

Endocrine conditions which may affect sexual function include:

• Thyroid disease (both hyperthyroidism and hypothyroidism).

• Type 1 diabetes mellitus.¹¹ Type 1 diabetes has a strong association with FSD.

• Type 2 diabetes mellitus.¹² Type 2 diabetes is particularly associated with disorders of arousal. Prevalence is highest amongst patients who also complain of depression.

• Women with Addison's disease have low levels of circulating androgens but, perhaps surprisingly, have not been found to report higher levels of FSD.¹³

• Polycystic ovary syndrome, obesity and metabolic syndrome could be associated with FSD but data are limited.¹⁴

Pregnancy¹⁵

The prevalence of FSD among pregnant women is reported in 50-80% of women, mainly in the first and third trimesters. Contributory factors are physical and hormonal changes, perceived loss of attractiveness, concerns about the baby, breast tenderness and vaginal dryness. Vulval discomfort may occur due to varicosities during pregnancy, and following delivery. For some women FSD resolves in the second trimester when the initial discomfort of the first trimester may have passed, and there can be an increase in libido and sexual pleasure.

Sexual dysfunction in the postpartum period¹⁶

Sexual function declines during pregnancy and does not return to its baseline levels during the postpartum period. Irrespective of the type of delivery, short-term postpartum sexual changes, such as dyspareunia and loss of desire, are highly prevalent in postpartum women. Perineal trauma and operative vaginal delivery are associated with increasing severity and incidence of dyspareunia.

Cardiovascular disease¹⁷

Cardiovascular disease (CVD) is associated with an increased prevalence of FSD. Atherosclerosis affecting the hypogastric/pudendal arterial bed decreases the blood flow to the clitoris and vagina; this is called clitoral vascular insufficiency syndrome. Decreased blood flow can result in the loss of corporal smooth muscle in the vagina and clitoris, followed by fibrosis.

Sexual dysfunction, like erectile dysfunction in men, is related to the severity of CVD. CVD has an effect on arousal/desire, sensitivity of the clitoris and vaginal labia, and orgasm. Women with heart failure are particularly prone to experience problems with vaginal lubrication and many report moderate to severe sexual pain.

Neurological factors¹⁸

Sexual desire/arousal and orgasm are mediated by central and spinal nerve pathways and involve sympathetic, parasympathetic and somatic nerve activity. Neurological conditions can therefore interfere with female sexual function. These include central conditions such as Parkinson's disease and stroke, spinal cord lesions, and peripheral conditions such as diabetic autonomic neuropathy and aortic aneurysm affecting the pelvic nerve plexuses.

The pelvic autonomic nerves are essential for normal sexual function. The sympathetic fibres arise over the sacral promontory. The parasympathetic fibres (pelvic nerves) originate from sacral roots of S2-S4. Sexual dysfunction after pelvic surgery is most commonly related to injury of the autonomic pelvic nerves.

Psychological factors¹⁸

Psychological factors (history of sexual abuse, depression, anxiety, obsessive-compulsive disorders), sociocultural issues (beliefs regarding sexual activity) and interpersonal issues (partner availability, partner function, relationship with partner, communication with partner) affect sexual function in all age groups. With ageing, additional psychological stresses may emerge, particularly loss of fertility, interruption of the menstrual cycle, the start of postmenstrual changes and altered body image. Gender identity issues and personal uncertainties about sexuality can surface at any age.

Chronic pain and illness¹⁹

Sexual difficulties in chronic pain are frequent and wide-ranging. Prevalence rates of sexual difficulties consistently range from 50-78%. Difficulties occur particularly with arousal, positioning, anticipation of pain, and lowered confidence. The partner's fear of triggering pain through sexual activity is significant, and complete cessation of sexual activity is reported in up to 40% of chronic pain patients.

Assessing pain is an important part of assessing FSD. Obvious examples which could benefit directly from targeted treatment would include pain affecting the joints, and conditions causing abdominal tenderness. Chronic or recurrent headaches, fibromyalgia and chronic fatigue syndrome, together with many types of cancer and the medical or surgical consequences of their treatment, can also lead to FSD.

Medication⁶

Medications that are associated with female sexual dysfunction include:

• Antidepressants (selective serotonin reuptake inhibitors, serotonin norepinephrine reuptake inhibitors, tricyclic antidepressants).

• Cancer therapies, especially for breast and gynaecological cancer.

• Antihypertensives, particularly beta-blockers.

• Antiepileptics.

• Benzodiazepines.

Under-researched groups

There is a relative gap in information regarding younger patients and regarding women whose symptoms fall outside the accepted definitions of FSD. These groups are less likely to present in primary care and may have different expectations of their sexuality.

Adolescent girls and female sexual dysfunction²⁰

Over half of adolescent girls are sexually active but research on FSD generally includes only women over 18 years of age. However, lack of sexual desire/arousal, sexual pain and anorgasmia are also likely to arise in adolescent girls, who are subject to many of the same factors that can affect older women. In girls these are more likely to be compounded by inexperience, lack of information and, often, lack of close partner trust. Sexually transmitted infections, condom allergies, congenital anomalies and abusive relationships should also be considered as possible underlying factors in this age group.

Persistent genital arousal disorder^{21 22}

Persistent genital arousal disorder is a condition of genital arousal in the absence of subjective sexual arousal. The physiological arousal can last hours or days, or occur constantly, and can arise through sexual or non-sexual stimuli. It does not remit after orgasm and is usually described by women as distressing, intrusive and unwanted. It is almost certainly under-reported, as it leads to confusion, shame and embarrassment, and a hesitation to seek help.

No cause or causes have been confirmed. Most literature consists only of case studies. A range of treatments, both pharmacological and psychological, has been tried successfully in isolated cases, including duloxetine and pregabalin. Identification of triggers, distraction techniques, and pelvic massage to decrease the pelvic floor tension have been attempted.

Risk factors⁶

The factors associated with an increased risk of FSD include increasing age, menopause (including premature ovarian failure), the postpartum period, genital surgery, genital atrophy, genital mutilation, sexual abuse, psychological factors, relationship problems, alcohol, substance use disorders, smoking, and obesity.

Medical and psychiatric conditions that are associated with female sexual dysfunction include:

• Cardiovascular disease.

• Diabetes mellitus.

• Neurologic disease (stroke, multiple sclerosis, spinal cord injury).

• Hypertension.

• Genitourinary syndrome of menopause.

• Breast, ovarian, uterine, and cervical cancer.

• History of gynaecological surgery.

• Chronic renal failure.

• Urinary incontinence.

Assessment of female sexual dysfunction³

The problem

As in all areas of practice, history begins with the problem, its nature, history and impact and anything the woman thinks may relate to any change.

It is important to identify which type or types of FSD are present: if pain is present this may drive the history towards organic causes, but there may be other contributing factors. Careful, open questions regarding particular sexual practices or positions which particularly trigger pain are needed. It is helpful to ask the woman whether she feels that lack of foreplay, short or long duration of intercourse, or sexual problems in her partner could be a factor in her FSD.

Ascertain whether the woman has ever been happy with her sexual function and, if so, what she feels has changed and whether the FSD is situation-specific or person-specific. In men we ask about morning erections as a guide to the integrity of the erectile function. In women there is no easy parallel. A change in the frequency of erotic thoughts and the ability to achieve orgasm alone may offer a guide to underling changes in physiology and libido. These questions should be approached with some sensitivity, as women may not expect to be asked them.

General history

This should focus on identifying organic risk factors for FSD. Sexual dysfunction in women is commonly related to physiological changes resulting from underlying conditions which may be straightforward to treat. The focus may vary somewhat with the age of the patient but may include:

• Cardiovascular risk factors.

• Smoking and alcohol.

• Drugs and medication.

• Sexual health history.

• Features suggestive of endocrine or neurological disease.

• General fitness, exercise and diet.

• Menstrual and contraceptive history.

• Obstetric and gynaecological history.

Psychological and relationship history

Again, careful, open questioning is needed, in part guided by what the patient wishes to discuss. Issues such as relationship difficulties, gender identity and sexuality, differing partner expectations and previous sexual abuse may be very difficult for patients to disclose but, conversely, offering a comfortable opportunity for them to do so may be very helpful. Questioning needs to be open and permissive, for example, 'Have you ever had sex when you didn't feel able to say no?'

Other relevant psychological factors can include mental health disorders such as anxiety, depression, post-traumatic stress disorder (PTSD) and eating disorder (with associated altered body image). Emotional factors include bereavement, lack of privacy, difficulties with cultural or religious expectations, and the presence of babies and small children in the home.

Examination³

Clinical evaluation will vary with the history. Where pain is a feature it is essential to exclude infectious disease, tumours, polyps and diseases such as endometriosis and pelvic inflammatory disorders. Genital examination may reveal significant prolapse, vaginal atrophy or scarring from episiotomy repair, or evidence of vaginismus.

Basic laboratory testing is helpful to rule out treatable conditions, and includes FBC, lipid profiles, renal and liver function, blood glucose and TFTs. Follicle-stimulating hormone, luteinising hormone, oestrogens and testosterone should be measured to assess the functional integrity of the hypothalamic-pituitary-gonadal axis. Other investigations, including imaging, will be guided by symptoms, particularly in cases of sexual pain.

Several self-reported questionnaires are available to assess sexual dysfunction. The Female Sexual Function Index²³ is the most commonly used validated questionnaire. It is a 19-item questionnaire. There are two other validated questionnaires that are available: the 22-item Brief Sexual Function Index and the 31-item Sexual Function Questionnaire.

Treatment and management of female sexual dysfunction^{6 24 25}

The management of FSD will depend on the predominant underlying causes and there will often be several. Traditionally a psychological-behavioural approach was recommended. However, increased awareness that the risk factors for FSD mirror those for erectile dysfunction in men illustrates that organic disease plays a significant role. New-onset FSD, like erectile dysfunction, is a possible flag for metabolic and cardiovascular disease, although the list of other possible contributing factors is long.

Treatment and management of any underlying cause or aggravating factor

Any potential cause needs to be assessment and optimal treatment provided - eg, genitourinary syndrome of menopause and sexual pain.

Non-pharmacological approaches

Behavioural interventions, particularly mindfulness-based therapies, have shown positive effects on sexual desire, sexual distress and overall sexual function. However, studies are relatively small, limited and lacking in comparison with pharmacological interventions.

Lifestyle advice²⁶
Whatever the underlying causes, general advice on health and well-being, and fitness, and lifestyle advice aimed at promoting cardiovascular health, including advice on smoking and alcohol, are likely to be helpful. Modifiable risk factors include obesity, lack of physical activity, poor diet, metabolic syndrome, smoking and excessive alcohol consumption.

Relationship counselling⁶
Where relationship issues or differing expectations form a part of the history and presentation, even if they are not felt to be the 'core' trigger, relationship counselling or psychosexual counselling can be very helpful. This has been the traditional route for treatment of FSD in the past, although it may be increasingly difficult to access from primary care.

Cognitive behavioural therapy
Psychotherapy may help remove inhibitions and enhance interpersonal relations and sexual motivation levels. Behavioural therapy in women with vaginismus leads to improvements in overall sexual functioning.

The sexual function of women with chronic pain can be significantly enhanced by a cognitive behavioural treatment group delivered within an interdisciplinary rehabilitation pain programme.¹⁹

Pelvic floor exercises²⁷
The role of the pelvic floor in arousal and orgasm is significant and women can easily be taught simple pelvic floor exercises. Several studies report improvements in desire, arousal, lubrication, orgasm and satisfaction with sex. Pelvic floor exercise is also helpful for postpartum FSD.

Pharmacological approaches to female sexual dysfunction

A number of different drugs are used to treat FSD but in the UK none is currently licensed for this indication. Flibanserin is now licensed in the USA for pre-menopausal women with hypoactive sexual desire disorder.⁶

Oestrogens²⁵ Oestrogens are the most commonly used medications for the treatment of FSD, especially in perimenopausal and postmenopausal women. There is good correlation between decreasing levels and sexual function. Oestrogen improves dyspareunia and vaginal pH. Oestrogen in postmenopausal women improves arousal, clitoral and vaginal sensitivity, lubrication and libido. Topical (vaginal) oestrogen improves vaginal dryness and irritation.

It is important to remember that replacement therapy with oestrogen (and progestogen) carries an increased coronary heart disease, stroke, thrombosis and breast cancer risk.

Testosterone ²⁸
Androgen levels in women decrease with age. Testosterone is one of the most frequently prescribed (off-label) medications for women with sexual interest/arousal disorder. However, its normal role in women is still not clear.

Testosterone has been studied for the treatment of hypoactive sexual desire disorder. Consistent positive effects have been found in sexual desire, overall sexual function, and sexual distress. Common adverse effects were acne and hirsutism, occurring in 5-20% of women. Analysis has suggested that only women who achieve supraphysiological levels of testosterone have a significant response. Studies have also suggested that there may be an increased risk of cardiovascular disease and invasive breast cancer when testosterone is added to traditional hormone therapy, but findings are inconsistent.

Transdermal testosterone patches and topical gels or creams are preferred over oral products because of first-pass hepatic effects documented with oral formulations. Testosterone products formulated for men have a risk of excessive dosing. Testosterone therapy is contra-indicated in women with breast or uterine cancer or in those with CVD or liver disease. It should be administered at the lowest dose for the shortest time that meets treatment goals.

Flibanserin^{29 30}

Flibanserin is a centrally acting drug which activates 5-HT1A receptors in the prefrontal cortex, increasing dopamine and adrenaline (norepinephrine) levels and decreasing serotonin levels. It has been described as a norepinephrine-dopamine disinhibitor (NDDI). Dopamine and norepinephrine are both involved in mediating sexual excitement, and serotonin is involved in sexual inhibition. Flibanserin is licensed for use for hypoactive sexual desire in pre-menopausal women in the USA. Women taking it are advised not to drink grapefruit juice and not to consume alcohol.

A review of eight studies (including 5,914 women) suggested that treatment with flibanserin, on average, resulted in one-half additional satisfactory sexual event per month over placebo, while significantly increasing the risk of dizziness, somnolence, nausea and fatigue. Overall, the quality of the evidence was graded as very low.

Phosphodiesterase type 5 inhibitors^{25 31}

The introduction of oral phosphodiesterase type 5 (PDE-5) inhibitors revolutionised the treatment of erectile dysfunction in men but they are not licensed for use in women.

The mechanism of clitoral engorgement differs from that in the penis in that there is no obstructive process enhancing tumescence - the clitoris is engorged by increased blood flow only. In smooth muscle cells, nitric oxide (NO) activates guanylate cyclase, which converts guanosine triphosphate into cyclic guanosine monophospate (cGMP). This promotes vasodilatation and increases blood flow in genital organs. PDE-5 inhibitors enhance production of guanosine monophosphate. PDE-5 is expressed in vaginal, clitoral and labial smooth muscles.

Early trials suggested that sildenafil improved the ability to achieve orgasm and arousal and could significantly improve clitoral blood flow in postmenopausal women with orgasmic dysfunction, although evidence has been mixed. A 2016 systematic review suggested that the use of PDE-5s resulted in significant improvements in sexual function compared with placebo.³² Adverse events include headache, and flushing and changes in vision are common.

Dr Mary Lowth is an author or the original author of this leaflet.