Female Sexual Function and Dysfunction
When most of us think of sex, we conjure up images of romance, love, and possibly lust. For the research scientist, though, there is talk of “the sexual response cycle” – desire, arousal, plateau, orgasm and resolution. We have the work of Masters and Johnson to credit (or blame) for this clinical approach to speaking of sex, but it serves a purpose as clinical trials are designed to study the needs and possible treatments for the woman complaining of decreased satisfaction with her sex life.
Research into medications for treatment of female sexual dysfunction remains in its infancy, but several companies are now viewing this as a promising area. Most current trials focus on the Desire or Arousal phases of sexual response, and a few focus on Orgasmic Disorder.
Sexual desire has been described as the motivation and the inclination to be sexual. Hypoactive Sexual Desire Disorder (HSDD) is defined as “the persistent or recurrent deficiency (or absence) of sexual fantasies/thoughts, and/or desire for or receptivity to sexual activity, which causes personal distress.” In other words, “I’m just not interested in sex, and I rarely think about having sex.”
In most clinical trials the focus is on women who previously had what they felt was a satisfying level of interest in sex, but who are distressed when they experience a decrease in interest. Women who have always had a low level of interest in sex are thought to be less likely to benefit from the medications currently being studied.
Sexual arousal is sometimes described as the “excitement phase” of the sexual response cycle. It is characterized by increased blood flow to the genital area with increased sensitivity and lubrication, and pleasant sensations, such as tingling in the breasts and other areas of the body. Sexual Arousal Disorder is defined as “the persistent or recurrent inability to attain or maintain sufficient sexual excitement, causing personal distress, which may be expressed as a lack of subjective excitement, or genital (lubrication/swelling) or other somatic responses.” In other words, “The desire is there, but my body just does not seem to respond.”
As with Desire Disorder, most clinical trials focus on women who are distressed when they notice a change from their previous experience with sexual arousal rather than on women who have never experienced satisfactory sexual arousal.
Sometimes when a woman complains of changes in sexual function, it is difficult to tell whether this is primarily a loss of interest, or whether a loss of interest occurs because the body does not respond as it once did. Often, as part of the assessment process in clinical trials, a Female Sexual Dysfunction expert will discuss these issues with the woman so that they can decide together which issue is the primary problem.
Orgasmic Disorder is “the persistent or recurrent difficulty, delay in or absence of attaining orgasm following sufficient sexual stimulation and arousal, which causes personal distress.”
Most clinical trials are not focused primarily on Orgasmic Disorder, but include patients who experience it as a result of Sexual Arousal Disorder.
Sexual Pain Disorders:
Sexual Pain Disorders involve recurrent or persistent genital pain associated with sexual intercourse. Treating these disorders depends on accurately diagnosing the cause of pain. For example, if pain is due to excessive thinning (atrophy) of vaginal tissues due to menopause, then the woman might qualify for trials on medications designed to correct the thinning. Other women may have pain due to a vaginal infection and would be candidates for a trial on vaginitis.