Male Sexual Health and the Sexual Act in Men

What is sexual health?

According to the World Health Organization, sexual health is a state of physical, mental and social well-being in relation to sexuality. It requires a positive and respectful approach to sexuality and sexual relationships, as well as the possibility of having pleasurable and safe sexual experiences, free of coercion, discrimination and violence. This applies to both males and females.

Ask a Doctor Online Now!

With regards to men, a more simplified definition is that sexual health is about being able to participate and enjoy in sexual acts with a partner in a manner that is fulfilling to both consenting parties. It is large subject that encompasses the physiological, psychological and social aspects of sexuality and sexual activity. For the purposes of this article, the focus will be largely on the physiological component of the male sexual act.

Stages of the Male Sexual Act

The male sexual act can be divided into four separate stages, each of which overlap with the preceding and successive stages. This broadly includes :

  • Stimulation / Arousal
  • Penile Erection
  • Lubrication
  • Orgasm -Emission and Ejaculation

Stimulation / Arousal

Arousal is a combination of both physical and psychological stimulation, although either one may be sufficient to continue to the next stage. Physical stimulation is via the more sensitive sensory areas like the glans penis. This is the erectile tissue that lies at the tip of the penis and is covered by the foreskin at times. Stimulation of the glans penis sends impulses through the pudendal nerve to the spinal cord (sacral segment) and up to the brain. The sensation that is perceived is sexual arousal or the ‘sexual sensation’.

The sensation may also be compounded by signals from adjacent sensitive areas like that of the scrotum, anus and perineal region. Stimulation of some of the internal organs – urethra, prostate, bladder, seminal vesicles, testes and vas deferens – may also contribute to this sensation. Local reflexes in the sacral and lumbar spinal cord can in some instances initiate and achieve an erection and even continue to ejaculation without any feedback from the brain. This has been demonstrated in humans after the spinal cord has been cut above the lumbar region.

The psychological component is not always as well understood, particularly in deviant sexual behavior. Sexual thoughts, images, sounds and even dreams can initiate the sexual act and lead to achievement of an erection and even ejaculation. It does play an important role despite the presence of local reflexes in the lumbar and sacral segments of the spinal cord. The psychological component can even inhibit many of the stages of the sexual act despite stimulation of the glans penis. This is seen in about 10% of men with erectile dysfunction (ED), where stress, depression and performance anxiety hampers the achievement and maintenance of a penile erection.

Erection

Impulses carried through the parasympathetic nerve fibers from the sacral portion of the spinal cord travel through the pelvic nerves to the penis. Here it stimulates the smooth muscle of the arteries and erectile tissue of the penis. Several neurotransmitters are involved at this neuromuscular junction, the most significant of which are nitric oxide, cGMP and cAMP. The smooth muscle then relaxes thereby increasing the blood flow to the penis and into the erectile tissue. The corpus cavernosa fills with blood which at the same time reduced the outflow of the blood. Filling of the sinusoids of the cavernosa causes the erectile tissue to balloon and the penis becomes hard and elongated.

With continued stimulation, the bulbocavernous reflex takes effect which causes the ischiocavernous muscles to contract forcefully. This causes rapid filling and expansion of the penis. Arterioles and venules are compressed shut and blood flow in and out of the penis ceases temporarily. The penis is now fully erect.

Lubrication

The lubrication stage starts with erection, sometimes as early as arousal even without an erection, and continues throughout the entire sexual act. This is mainly facilitated by the urethral and bulbourethral glands. Mucus is secreted out of the urethra and lubricates the tip of the penis. During intercourse this penile secretions in conjunction with females secretions from the vaginal epithelium and Bartholin’s gland aids with lubrication. In fact most of the lubrication for intercourse is from the from the female secretions.

Male Orgasm

The male orgasm is made up of two phases Рemission and ejaculation Рwhich  form the last stage of the male sex act.

Once the sexual stimulation during intercourse reaches a certain intensity, the emission phase begins. Impulses transmitted via sympathetic fibers reach the spinal cord between T12 to L2 and return through the pelvic sympathetic nerve plexus as well as the hypogastric plexus.This causes the vas deferens to contract and sperm is pushed into the internal urethra. The prostate gland passes out prostatic fluid and the seminal gland expels seminal fluid. These fluids along with the sperm and mucus mix to form semen. This process is known as b.

When semen fills the urethra it stimulates receptors which sends impulses to the sacral portion of the spinal cord via the pudendal nerve. This is perceived as a sensation of fullness within the groin. The internal genital organs are stimulated by these sensations and this causes the ischiocavernous ad bulbocavernous muscles to contract and relax repeatedly. The rhythmical contractions causes a pressure wave to travel through the erectile tissue of the penis and the semen is forced out into the exterior. This process is known as ejaculation.

Detumescence

Although this is not a separate phase of the male sexual act, it is worth understanding. The male sexual act technically ends with ejaculation but the gradual ‘deflation’ of the penis known as detumescence is an important component in the physiology. At the end of the male orgasm, sexual excitement subsides and disappears completely within a few minutes in a process known as resolution. There is simultaneous restoration of normal blood flow to the penis. The very same sympathetic stimuli that initiates the orgasm is responsible for restoring the blood flow. Neurotransmitters at the neuromuscular junction, which facilitate the penile erection, are broken down by the phosphodiesterase enzyme (PDE). This enzyme is an important target for erectile dysfunction drugs. Blood empties out of the erectile tissue and the penis gradually becomes flaccid. This is known as detumescence.

Please note that any information or feedback on this website is not intended to replace a consultation with a health care professional and will not constitute a medical diagnosis. By using this website and the comment service you agree to abide by the comment terms and conditions as outlined on this page

Ask a Doctor Online Now!