Chapter 16: Sexual Dysfunctions and Paraphilic Disorders

INTRODUCTION

Sexual dysfunctions include clinically significant disturbances in individuals’ ability to respond sexually or to experience sexual pleasure.

SEXUAL RESPONSE CYCLE

There are several stages of normal sexual response in men and women:

1. Desire: The motivation or interest in sexual activity, often reflected by sexual fantasies.

2. Excitement/Arousal: Begins with either fantasy or physical contact. It is characterized by erections and testicular enlargement in men and by vaginal lubrication, clitoral erection, labial swelling, and elevation of the uterus in the pelvis (tenting) in women. Both men and women experience flushing, nipple erection, and increased respiration, pulse, and blood pressure.

3. Orgasm: In men just prior there is tightening of the scrotal sac and secretion of a few drops of seminal fluid. Women experience contraction of the outer one-third of the vagina and enlargement of the upper one-third of the vagina.

4. Men ejaculate and women have contractions of the uterus and lower one-third of the vagina. There is facial grimacing, release of tension, slight clouding of consciousness, involuntary anal sphincter contractions, and acute increase in blood pressure and pulse in both men and women.

5. Resolution: Muscles relax and cardiovascular state returns to baseline. Detumescence of genitalia in both sexes. Men have a refractory period lasting minutes to hours during which they cannot reexperience orgasm; women have little or no refractory period.

SEXUAL CHANGES WITH AGING

The desire for sexual activity does not usually change as people age. However, men usually require more direct stimulation of genitals and more time to achieve orgasm, with less reliable/strong erections. The intensity of ejaculation usually decreases, and the length of refractory period increases.

After menopause, women experience vaginal dryness and thinning due to decreased levels of estrogen and lubrication. They may also have decreased libido and reduced nipple/clitoral/vulvar sensitivity. These conditions can be treated with hormone replacement therapy or vaginal creams.

DIFFERENTIAL DIAGNOSIS OF SEXUAL DYSFUNCTIONS

Problems with sexual functioning may be due to any of the following:

• Medical conditions: Examples include atherosclerosis (causing erectile dysfunction from vascular occlusion), diabetes (causing erectile dysfunction from vascular changes and peripheral neuropathy), and pelvic adhesions (causing dyspareunia in women).

• Medication side effects: Antihypertensives, anticholinergics, antidepressants (especially selective serotonin reuptake inhibitors [SSRIs]), and antipsychotics.

• Depression.

• Substance use.

• Abnormal levels of gonadal hormones:

  • Estrogen: Decreased levels after menopause cause vaginal dryness and thinning in women (without affecting desire).

  • Testosterone: Promotes libido (desire) in both men and women.

  • Progesterone: May inhibit libido in both men and women by blocking androgen receptors; found in oral contraceptives, hormone replacement therapy, and, occasionally, treatments for prostate cancer.

• Presence of a sexual dysfunction (see below).