Men's Health: Detailed Explanation of Ejaculation Physiology, Causes of Premature Ejaculation, and Scientific Treatment Recommendations

Ejaculation and Ejaculatory Disorders

Ejaculation is an independent reflex activity, accomplished through a series of coordinated movements of various parts of the urogenital tract. Afferent impulses originate from the frictional stimulation of the glans penis. Once a certain intensity (or threshold) is reached, the afferent nerves excite the lower reflex centers of the lumbosacral spinal cord, initiating the ejaculation process.

The entire ejaculation process consists of two stages. In the first stage, the smooth muscles of the epididymis, vas deferens, prostate, and seminal vesicles contract in a specific sequence, propelling semen into the posterior urethra. Simultaneously, the sphincter muscles of the bladder shaft and the internal urethral orifice contract to prevent semen from entering the bladder or urine from entering the urethra. In the second stage, the ischiocavernosus and bulbospongiosus muscles of the perineum, along with other perineal muscles, rhythmically contract, generating the force for semen ejection and allowing it to be smoothly expelled from the body through the urethra. Ejaculation occurs during orgasm, usually after sufficient local stimulation in an erect state; however, ejaculation and erection are two completely independent components of sexual arousal. Sometimes erection and local stimulation do not accompany ejaculation, while other times, stimulation of the ejaculation center in the spinal cord can induce ejaculation without local stimulation or erection. Clinical and life experience also shows that men can ejaculate based on fantasies even without external stimulation, such as nocturnal emission. Conversely, fear and fantasy can inhibit ejaculation. Rhythmic sexual stimulation of the glans penis and shaft is an important condition for the ejaculation reflex. Without sufficient stimulation, the ejaculation center in the spinal cord cannot be excited, and the ejaculation process cannot be initiated or completed. This is a major reason why some men do not ejaculate during sexual intercourse.

Because everyone's physical condition and responsiveness to sexual stimulation are different, the amount of stimulation required to trigger the ejaculation reflex varies greatly from person to person. Some men need strong and repeated penile-vaginal friction to reach orgasm and ejaculation, while some men (especially newlyweds or couples living apart) can ejaculate with only slight local stimulation, resulting in a short erection time and sometimes failing to satisfy their partner's sexual needs. Some men experience premature ejaculation or premature ejaculation due to local pathological changes, such as phimosis, balanitis, urethritis, prostatitis, and seminal vesicle inflammation. These conditions can weaken tolerance to local stimulation, leading to premature ejaculation or short erection time. These men need to consult a doctor for examination and targeted treatment.

Men generally experience a strong sense of euphoria during ejaculation. After ejaculation, semen remains in the posterior part of the vagina near the cervix, which is beneficial for the partner's conception. After ejaculation, most men enter a refractory period to sexual stimulation. With age, the frequency and volume of ejaculation gradually decrease, and the force of semen expulsion (i.e., the force of perineal muscle contraction) also gradually weakens. Sometimes, the semen is not felt to be expelled with rhythmic muscle contractions, but rather flows slowly from the urethra without any sensation. Some older men, due to reduced semen production, may experience difficulty ejaculating or anejaculation during intercourse; these are all signs of age-related sexual dysfunction. Some medications can improve these symptoms, but they should not be used blindly; it is best to use them under the guidance of a specialist.

Ejaculatory disorders are mainly characterized by premature ejaculation and anejaculation.

Premature Ejaculation (or Ejaculatory Dysfunction)

Premature ejaculation, sometimes called premature ejaculation, is a common symptom of male sexual dysfunction. Approximately one-quarter to one-third of married men have experienced or are constantly troubled by it to varying degrees. Most couples, after a period of time after marriage, through mutual understanding and adaptation, and after gaining experience in sexual intercourse, can quickly find ways to achieve mutual orgasm and harmonious sexual relations.

For many years, many scholars and experts have attempted to establish a diagnostic standard for premature ejaculation, but this standard is difficult to determine. This is because there are significant individual differences; the response speed, intensity, and duration to the same stimulus will not be entirely the same. Some couples can achieve mutually satisfactory results in just 3-5 minutes during sexual intercourse, while others may not experience orgasm even after more than ten minutes. A survey conducted by Zhejiang Medical University on the sexual experiences of 2709 individuals revealed that most intercourse lasted 5-10 minutes, with some lasting 1-2 minutes and others as long as 50-60 minutes. Such a large variation means that rigidly defining intercourse lasting less than 2 or 3 minutes as premature ejaculation would inevitably exclude a large number of healthy individuals from the medical field.

Currently, many experts consider ejaculation to occur before or immediately after penetration. Some scholars, however, believe that regardless of the duration of penetration before ejaculation, as long as it doesn't affect the experience of sexual pleasure for both partners and achieves sexual arousal and satisfaction, it should be considered normal.

Many factors contribute to premature ejaculation, but a significant proportion of patients suffer from functional or habitual rapid ejaculation. These patients experience a rapid progression from sexual arousal to orgasm and are abnormally sensitive to the ejaculatory reflex. Past sexual experiences and psychological factors also play a role. Dissatisfaction with sexual life and anxiety can trigger a reflexive rapid ejaculation response. In addition, local organic diseases are also a significant cause of premature ejaculation, such as chronic cystitis, prostatitis, seminal colliculitis, and urethritis. Inflammation and congestion can reduce the tolerance of local tissues to sexual stimulation, leading to premature ejaculation. Phimosis (tight foreskin) can also be a cause of premature ejaculation. In patients with phimosis, the glans penis is constantly covered by the foreskin, reducing its contact with the outside world. The nerve endings in the glans are highly sensitive to various stimuli, easily reaching the stimulation level required for ejaculation, resulting in premature ejaculation. Therefore, patients with premature ejaculation should not put too much psychological pressure on themselves. They should first look for the problem within themselves. If it is due to a functional cause, self-training under the guidance of a doctor can solve the problem. If it is caused by a local disease, they should promptly consult a doctor and never blindly use medication.