Humans are sexual beings from birth until death. Sexuality is an integral aspect of our personalities and is more than sexual contact and the ability to reach sexual satisfaction. Sexuality includes views of ourselves as male or female, feelings about our bodies, and the ways we communicate verbally and nonverbally our comfort about ourselves to others. It also includes the ability to engage in satisfying sexual behaviors alone or with another. Sexuality does not end when one reaches a certain age, nor does it end with the diagnosis of a chronic illness. In fact, sexuality and intimacy may become more important after such a diagnosis as a way of reaffirming human connection, aliveness, and continued desirability and caring. Sexuality is a critical aspect of quality of life that, unfortunately, is often ignored by healthcare professionals.
This chapter briefly reviews standards of nursing practice as they relate to sexuality, sexual physiologic functioning, alterations in sexuality caused by common chronic illnesses and their treatments, and nursing interventions. This chapter also provides nurses with suggestions for ways to incorporate discussions of sexuality into their practice.
The Sexual Response Cycle and Sexual Physiology
There are two frameworks commonly used to describe what is called the “sexual response
cycle.” The first, proposed by Dr. William Masters and Virginia Johnson (1966), is a fourstage model of sexual response of the male and female. The four phases of the
Masters and Johnson (1966) model are excitement, plateau, orgasm, and resolution. The excitement stage causes an increase in the heart rate and vasocongestion to the penis. This is accompanied by lengthening and widening of the vagina, elevation of the cervix and uterus, and initial swelling of the labia minora (
Guyton & Hall, 2006;
Masters & Johnson, 1966). These changes are caused by vasocongestion and are secondary to a parasympathetic response mediated to S2 and S4 through the pudendal nerve and sacral plexus (
Guyton & Hall, 2006).
The second stage is the plateau stage, which is an increased state of arousal causing the heart rate and blood pressure to increase, with a subsequent increase in respiratory rate (
Katz, 2007). The third stage is the orgasm, the phase of maximal muscular contraction (male ejaculation, and female pelvic muscle contraction), with a peak of respirations and heart rate, and a subjective feeling of intense pleasure that radiates throughout the body (
Katz, 2007). Impending orgasm is determined by the presence of an intense color change in the labia minora in women and full elevation of the scrotal sac to the perineal wall in men, all a result of intense vasocongestion (
Masters & Johnson, 1966). Orgasm is mediated by the sympathetic nervous system and is the physical release and peak of pleasurable expression, followed by relaxation (
Guyton & Hall, 2006). The sympathetic nerves between T12 and L2 control ejaculation (
Koukouras et al., 1991). The intensity of orgasm in women is dependent upon the duration and intensity of sexual stimulation.
The final stage is resolution, when vasocongestion resolves and the body returns to its normal nonaroused state (
Katz, 2007). Men also have what is referred to as a “refractory period,” which is the period within which the male is unable to achieve an erection satisfactory for penetration. This period of time is age and health-status dependent (
Masters & Johnson, 1966).
Physical changes that occur in both men and women as a result of sexual stimulation are vasocongestion and myotonia. Vasocongestion occurs in the penis in men and in the labia in women, and is an essential requirement for orgasm and subsequent sexual satisfaction. Myotonia refers to the involuntary muscular contractions that occur throughout the body during sexual response (
Kolodny, Masters, Johnson, & Biggs, 1979).
The second framework is from
Kaplan. Kaplan’s (1979) modification of the sexual response cycle includes aspects of sexual physiology involving the prelude to sexual activity as well as the consequences of sexual activity. These three phases are desire, arousal, and orgasm. Desire is the prelude to engaging in satisfying sexual behaviors and is the most complex component of the sexual response cycle. Desire is often affected by factors such as anger, pain, and body image, as well as disease processes and medications (
Kaplan, 1979). When sexual stimuli are perceived by women, they are processed physiologically and physically, leading to subjective feelings of arousal and a responsive feeling of desire (
Katz, 2007). This may explain why psychogenic factors can be a determinant cause of male and female sexual dysfunction.
Arousal, manifested by erection in males, is mediated by the parasympathetic nervous system and is the result of either psychic or somatic sexual stimulation (
Masters & Johnson, 1966). Alternately, activation of the sympathetic nervous system will lead to loss of an erection through vasoconstriction. It was previously thought that an analogous process of parasympathetic nervous system stimulation led to arousal in women. However, evidence suggests that it is stimulation of the sympathetic nervous system (SNS) that is responsible for female arousal (
Meston, 2000). Data also suggest that stimulation of the SNS may enhance arousal in women with low sexual desire (
Meston & Gorzalka, 1996) and that induction of relaxation may negatively affect arousal (
Meston, 2000).
Although many women suggest that the Gräfenberg spot (G-spot) plays an important role in their sexuality, the existence of this sensitive
area remains open for verification (
Hines, 2001). The G-spot is purportedly located in the anterior wall of the vagina, about halfway between the back of the pubic bone and the cervix along the course of the urethra (
Ladas, Whipple, & Perry, 1982). When stimulated, this tissue swells from the size of a bean to greater than a half dollar (
Ladas et al., 1982). Stimulation of this area appears to cause a different orgasmic sensation, and it is hypothesized that this response is mediated by the pelvic nerve, causing the uterus to contract and descend against the vagina rather than elevate, as with stimulation mediated by the pudendal nerve (
Ladas et al., 1982). Approximately 40% of women will experience expulsion of a fluid upon orgasm caused by G-spot stimulation (
Darling, Davidson, & Conway-Welch, 1990). Research suggests that this is a prostatic-like fluid that is released during orgasm (
Zaviacic & Whipple, 1993;
Zaviacic & Ablin, 2000). Belief that this is not urine but a normal release of fluid that occurs during sexual response may lead to a reduction in embarrassment for many women.
The neurohormonal system influences sexual functioning through its effect on hormone production. The hypothalamic-hypophysial portal system plays an important role in sexual functioning in both genders through production of gonadotropin-releasing hormone (GnRH) and subsequent stimulation of gonadotropin production by the anterior pituitary gland. The anterior pituitary gland secretes six hormones, two of which play an essential role in sexual functioning. Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) control growth of the gonads and influence sexual functioning. In men, LH influences production of testosterone by the Leydig cells in the testes through a negative feedback loop (
Guyton & Hall, 2006). Production of GnRH is reduced, once a satisfactory level of testosterone has been attained. A negative feedback loop also exists in the woman, although it is much more complex, given the concurrent production of estrogen and progesterone by the ovary and the production of androgens by the adrenal cortex.
Psychic factors appear to play a larger role in the sexual functioning in women than in men, particularly in relation to sexual desire. Multiple neuronal centers in the brain’s limbic system transmit signals into the arcuate nuclei in the mediobasal hypothalamus. These signals modify the intensity of GnRH release and the frequency of the impulses (
Guyton & Hall, 2006). This may explain why desire in women is more vulnerable to emotions and distractions than it is in men.
Aging affects the sexual response cycle in predictable ways, but it does not signal the end of sexuality. In fact, the old adage, “use it or lose it,” is applicable to continued sexual activity throughout life (
Masters & Johnson, 1981). The general impact of aging on the sexual response cycle is a slower, less intense sexual response (
Lindau, Schumm, Gaumann, Levinson, O’Muircheartaigh, & Waite, 2007). The frequency of sexual activity in earlier years is predictive of frequency as one ages. The quality of the sexual relationship appears to be the greatest influence on the frequency and satisfaction of sexual activity (
Masters & Johnson, 1981). As in younger adults, the quality of communication in a relationship, degree of mutual intimacy, and level of commitment to the relationship are vital to a satisfying sexual relationship and to achieving sexual satisfaction.
In clients aged 60 or older, organic factors are the most important determinant of erectile dysfunction (
Corona et al., 2007). The frequent
comorbidity of multiple metabolic and hemodynamic abnormalities in aging clients can substantially increase the incidence and progression of atherosclerotic lesions, leading to vascular forms of erectile dysfunction (
Corona et al., 2007).
Masters and Johnson (1966) found that in men between 51 and 90 years of age, the time to achieve erection was two to three times longer than in younger men. Achieving erection also required more tactile stimulation than in younger years. However, once achieved, older men can maintain a full erection for a longer period before ejaculation. Scrotal vasocongestion is reduced, with a subsequent decrease in testicular elevation. Basal and dynamic peak cavernosal velocity was shown to be reduced in older patients via Doppler ultrasound penile examination (
Corona et al., 2007). The ability to attain orgasm is not impaired with aging, but there is an overall decrease in myotonia and fewer penile and rectal sphincter contractions. There is an increase in time from hours to days before older men can achieve another erection once they have ejaculated and achieved an orgasm (refractory period).
Women also experience sexual response cycle changes as they age, primarily after completing the menopausal transition. Common complaints include decreased desire, dry vagina, and difficulty attaining orgasm (
Lindau et al., 2007). Vaginal changes include a thinning of the mucosa, with a decrease in vaginal lubrication. In women who abstain from sexual intercourse, narrowing and stenosis of the introitus and vaginal vault can occur (
Leiblum & Segraves, 1989). Older women experience a decrease in the vasocongestion of the labia and other genitalia analogous to the decrease in penile tumescence experienced by men. Orgasm in sexually active women is not impaired; however, there is some decrease in the degree of myotonia experienced. Intense orgasm may lead to involuntary distension of the external meatus, leading to an increase in frequency of urinary tract infections in older women.
