What is sexual dysfunction?

The term "sexual dysfunction" broadly encompasses trouble with any component of the sexual response cycle. The sexual response cycle in men consists of sexual desire/interest (libido), sexual arousal (erection), orgasm (including emission [involuntary discharge of semen from the ejaculatory duct into the urethra] and ejaculation), and detumescence (return of the penis to the flaccid, nonerect state). An abnormality in one component of the sexual response cycle may not affect the remainder of the components of the cycle. For example, one may still be able to climax and ejaculate without achieving a rigid erection. Common sexual dysfunctions include problems with libido, ejaculation, and orgasm.

Libido

Lack of interest in sex is often called decreased libido or decreased desire. Libido is governed by psychogenic factors and involves all five senses (sight, smell, taste, touch, and hearing) as well as hormonal factors. Low libido, or hypoactive sexual desire, occurs in about 15% of men and in about 20% of the general population, both men and women. Depression and anxiety may adversely affect one's libido, and depression is the leading cause of hypoactive sexual desire. Other causes of hypoactive desire include relationship factors: lack of trust, intimacy conflicts, and lack of physical attraction to one's partner. The hormone testosterone is the main hormone responsible for libido in men. Testosterone levels have an effect on libido and on sexual thoughts and fantasies.

Sexual Arousal (Erection)

Sexual arousal requires input from nerves and arteries. To achieve an adequate erection, there must be at least six times as much blood flow into the corpora cavernosa. Changes in nerves, arteries, and veins may lead to trouble with erections. The Massachusetts male aging study demonstrated that approximately 52% of males have some degree of erectile dysfunction between the ages of 40 and 70.

Ejaculation

Ejaculatory dysfunction includes premature ejaculation, retrograde ejaculation, delayed ejaculation, and anejaculation. Premature ejaculation means that ejaculation occurs too quickly and may occur with light stimulation before, on, or shortly after penetration, or simply before one wishes for it to occur. Retrograde ejaculation is a condition in which the ejaculate passes backward into the bladder; this condition may be associated with decreased ejaculate volume or no ejaculate. Delayed ejaculation is a condition in which it takes too long to ejaculate; it is frequently associated with the use of the newer antidepressants, the SSRIs. Anejaculation is a condition in which no ejaculation occurs at all.

Anorgasmia (complete absence of orgasm) occurs in 17% of married men and affects younger men more commonly.

Orgasm

Orgasm is another term used for sexual climax, or the culmination of sexual excitement. Orgasmic dysfunction refers to alterations in orgasmic function or the inability to achieve an orgasm, to climax. Anorgasmia (complete absence of orgasm) occurs in 17% of married men and affects younger men more commonly. Psychological causes of anorgasmia include fear of pregnancy or AIDS, anxiety disorders, and repressive cultural, parental, or religious attitudes toward sexuality.

How does one diagnose and evaluate ED?

The diagnosis (identification of the cause or presence of a medical problem or disease) and evaluation of ED require a thorough history, complete physical examination, and possibly some laboratory testing. At first, your doctor will want to establish that the problem truly is ED and not some other form of sexual dysfunction (see Question 68). Your doctor may start the visit out by first paraphrasing the definition of ED— the consistent inability to achieve and/or maintain an erection satisfactory for the completion of sexual performance—to make sure that you are both discussing the same problem. Your doctor will also need a history, which will involve asking a number of questions about your medical, social, and sexual background. Some of these questions might be uncomfortable or embarrassing, but you should answer them as honestly as possible because this is probably the most important part of the diagnostic process, allowing the physician to identify common risk factors for both organic (having a physical origin) and psychogenic (originating from the mind or psyche) erectile dysfunction.