Physiology of Ejaculation
Ejaculation is the final phase of sexual cycle, usually accompanying orgasm in a man. It is a reflex uniting sensory receptors, centers for controlling brain and spinal cord and efferent pathways.
Ejaculation is a reflex that requires complex interaction between somatic, sympathetic and parasympathetic pathways, including predominantly central dopaminergic and serotonergic neurons.
Ejaculation includes 2 phases:
- accumulation (emission);
In the first phase, sympathetic nervous system participates, and the phase is determined by accumulation of seminal fluid in posterior urethra. Expulsion is associated with joint interaction of sympathetic and somatic nerve pathways. Ejaculation requires synchronous interaction between periurethral muscular contractions and closure of neck of the bladder simultaneously with relaxation of external sphincter of the bladder. Orgasm is usually associated with ejaculation. This pleasant sensation as a result of cerebral processing of raised pressure in posterior urethra and compression of bulbous urethra.
Coordination of Ejaculation
Adequate stimulation of dorsal nerve receptors of penis and posterior urethra is sufficient for development of ejaculation. Emission of seminal fluid is controlled by sympathetic nervous system, which contracts smooth muscles of prostate gland, vas deferens and seminal vesicles. Also, sympathetic nervous system enhances secretion of prostate gland.
Role of parasympathetic nervous system in ejaculation is not yet clear. Somatic nervous system (pudendal nerve) responds exclusively for ejaculate expulsion phase, synchronizing work of ischium-cavernous muscle, bulbose muscle, abdominal wall muscles, perineum, urethral and anal sphincters.
At spinal cord injury in the region of S II-IV segment or patients with neuropathy (diabetes) usually have weak innervation of pelvic floor muscles, which appears due to lack of normal ejaculation.
Neuropharmacology of Ejaculation
Experimentally, it was proved that dopamine and serotonin play the main role in regulation of ejaculation.
Definition of Premature Ejaculation
There are several definitions of rapid ejaculation.
Definition by International Society for Sexual Medicine (ISSM):
Premature ejaculation occurs within 1 minute.
There is no possibility to delay ejaculation.
Ejaculation occurs before or during introduction of penis into vagina.
Negative attitude of partner and a man himself to rapid ejaculation.
Definition by WHO 2010:
There is no ability to delay ejaculation, ejaculation occurs within 15 seconds or less from the moment of introduction of penis into vagina.
There is no possibility of enjoying sexual relations.
Definition by American Urological Association (AUA):
Ejaculation occurs earlier than a man would like.
Appears quickly enough after introjection (penetration of penis into vagina). This is the cause of suffering of one or both partners.
Definition by European Association of Urologists (EAU):
Impossibility to control ejaculation for sufficient time before introduction into vagina.
Definition by American Psychiatric Association (APA):
This is permanent or periodic ejaculation with minimal sexual stimulation, occurs before introduction of penis into vagina or soon after it. Ejaculation occurs before a man wants it.
Definition by Master and Johnson – published in the book «Human Sexual Inadequacy»:
Premature ejaculation is inability to control ejaculation for a sufficient time during sexual intercourse and inability to satisfy partner in at least 50% of cases of sexual intercourses.
Of all definitions three components are distinguished:
- premature ejaculation always or almost always occurs within 1 minute after penetration into vagina;
- inability to delay ejaculation after penetration into vagina;
- negative attitude of both sex partners to sexual relations or complete rejection of sex.
In 2007, classification of rapid ejaculation was proposed, where patients were divided into 4 types:
- lifetime type – premature ejaculation occurs in all or most sexual intercourses and with different partners. In most cases, ejaculation occurs within 1 minute. Ability to control ejaculation may be absent;
- acquired type – premature ejaculation occurs during sexual activity. Patient notes presence of period of normal ejaculation. The cause of premature ejaculation is not found (organic and mental causes). Ability to control ejaculation may be absent.
- natural (variable) type – premature ejaculation is impermanent and irregular. Ability to control ejaculation may be absent.
- premature ejaculation as a dysfunction – rapid ejaculation is subjective. Intravaginal time of sexual intercourse – in normal range. Patient is concerned about lack of control over ejaculation. Sexual hyperactivity is not considered a sign of mental illness. Ability to control ejaculation may be absent.
Premature Ejaculation – Epidemiology
In a multicenter study, self-esteem of time required for average duration of sexual intercourse varies from 7 to 14 minutes. Average duration of sexual intercourse in Germany is 7 minutes, in the USA – 14 minutes, in England, France and Italy – 10 minutes.
Thus, prevalence of premature ejaculation is approximately 20 – 30% and is most common in young men.
Effect of Premature Ejaculation on Life of a Man
Premature ejaculation affects emotional and relational levels. A man has feeling of shame and embarrassment about lack of opportunity to satisfy his partner. Often, he has low self-esteem and inferiority complex.
The main problem for patients with premature ejaculation is destruction of sexual confidence. Global studies of sexual relations and behavior have shown that sexual experiences with rapid ejaculation can lead to depression.
Increase in duration of sexual intercourse is an important factor for men who need treatment for PE. Patients with PE face difficulties in initiating and supporting relationships with the opposite sex. Women in pairs experience anxiety due to weak ejaculation control, which leads to sexual dissatisfaction.
Premature Ejaculation – Causes of Development
The study, devoted to premature ejaculation, showed significant negative impact on psychological state of the patient and his partner. Biological mechanisms involved in the process of ejaculation give a deep understanding of pathophysiology of PE development at present time. Despite this, gaps remain in the genesis of PE.
The main reasons for development of PE:
- hormonal aberration;
- sensory changes in penis;
- chronic prostatitis.
For the first time in 1940 Shapiro noted family predisposition to PE. After 50 years, this statement was confirmed. The study of twins confirms the factor of genetic nature of PE.
At present, it is suggested that sympathetic nervous system is activated during anxiety. During sexual intercourse sympathetic NA leads to earlier ejaculation.
The study of psychological factor confirmed direct relationship between stress at work, problems in personal relationships and PE. Psychological factor confirmed that in men with rapid ejaculation there is hyperexcitable ejaculation reflex. Currently, studies are conducted on impact of psychological factors on rapid ejaculation.
One of the most studied hormones in the genesis of premature ejaculation is leptin protein. Leptin was opened in 1994. As OD-gene product. Its main role is to provide information on amount of fat in hypothalamus, thus modulating functions of central nervous system regulating food intake and energy balance. Leptin level in blood serum in patients with PE is significantly higher than in patients with normal ejaculation.
Citalopram was used to reduce level of leptin, with decrease in level of leptin possibility of controlling ejaculation changed. In studies of blood serum for gonadotropin in patients with rapid ejaculation and healthy men, there were no significant differences.
Although testosterone level in patients with rapid ejaculation was higher than in men who can control ejaculation. Also, other studies have noted a link between hyperprolactinemia and fast ejaculation.
In other studies of hormonal status, evidence of hyperthyroidism in patients with rapid ejaculation was noted. In patients with hyperthyroidism after thyroidectomy, radiotherapy and drug therapy, ejaculation rates were restored in 25% of cases.
At present, role of hormones in development of PE has not been fully studied.
Penis Sensitivity and Circumcision
There are not so many topics in urology that generate a lot of controversy. Effect of circumcision of foreskin on duration of sexual intercourse is such a topic. This topic is well studied, but the data are contradictory. Theoretically, circumcision leads to keratinization of balanus, which potentially reduces sensitivity of the penis balanus.
Some authors have reported high sensitivity of penis in uncircumcised men. Lauman and colleagues in the studies demonstrated beneficial effect of circumcision on sexual function of men.
When carrying out thermal and vibration sensitivity in patients with premature ejaculation, there was a higher threshold of vibration sensations (decreased sensitivity) compared to men who can control ejaculation.
Some authors studied dependence of development of PE on condition of genital tract of partner (parous and nonparous women). Absolutely accurate data on this dependence was not found.
A number of studies were aimed at studying effect of chronic prostatitis on development of PE. As a result of these studies, mechanisms responsible for association of chronic prostatitis and premature ejaculation have not been detected.
Premature Ejaculation – Examinations
Sexual history: in spite of negative impact of erectile dysfunction associated with rapid ejaculation, only 15% of patients reported to doctor about this problem.
American Urological Association (AUA) recommended urologist to actively be interested in sexual health and offer each patient fill out anonymous questionnaire (IELT).
It is also recommended to take into account the following issues:
- duration and frequency of PE;
- frequency of occurrence of rapid ejaculation with one or different partners;
- what sexual stimulation causes rapid ejaculation;
- nature and frequency of sexual activity, which includes foreplay, masturbation and sexual intercourse.
Despite many definitions of the term PE, most precise definition is given by ISSM. To establish diagnosis of PE, not only stopwatch data and IELT test results should be taken into account. Be sure to take into account patient’s anamnesis, duration of PE and subjective assessment of the degree of ability to control ejaculation. An important factor in questioning a patient is to differentiate PE from erectile dysfunction, because in patients with weak erectile function and inability to maintain erection for a long time, PE is a symptom of these diseases.
When examining patients with rapid ejaculation, routine medical examination and spermogram analysis are not enough. It is necessary to assess signs and symptoms of premature ejaculation, thyroid function studies, studies recommended for HP, routine examination of genital organs, assessment of sacral reflexes and neuromuscular reflexes of the lower extremities.
For evaluation questionnaires can be used:
- PE Profile (PEP);
- Index of PE Johnson & Johnson (IPE);
- Questionnaire of male sexuality ejaculation;
- PE: Diagnostic device. Powered by Pfizer.
Premature Ejaculation Treatment
- Described by urologist James Semans in 1956, the technique consisted in stimulation of penis, at the period of possible orgasm there was a sharp stop, delay of ejaculation.
- Stop-start method. The main method of treatment was proposed in 1970 by Masters and Johnson, a partner of the patient was recommended at the time of onset of possible orgasm to press penis with hands in the bridle area for 30 seconds. The method is known as «compression technique».
Both methods are aimed at revealing precursors of ejaculation. According to some data, effectiveness of these methods is 45 – 60%.
Preparations of central action: clomipramine, paraxetine, fluoxetine, sertroline, fluvoxamine, dapoxetine, tramadol, phosphodiesterase type 5 inhibitor.
Selective resection of spinal nerves. Selective neuroectomy of dorsal nerve of penis.
- Diagnosis of premature ejaculation is based on careful collection of sexual history. It is extremely important to distinguish PE from erectile dysfunction. It is important to take into account self-evaluation of duration of sexual intercourse by a man and degree of anxiety.
- Use of additional instrumental survey methods.
- Use of behavioral therapy.
- Combination of pharmacotherapy and psychotherapy.