Ejaculation has three phases — emission (sympathetic, T10–L2), ejection/expulsion (somatic pudendal, S2–S4), and orgasm (central) — and disorders arise when any is disrupted. Premature ejaculation is the commonest male sexual dysfunction; delayed, retrograde, and absent ejaculation usually follow surgery, medication, or neuropathy.
Normal Ejaculation
- Emission — sympathetic (T10–L2) contraction of the vas, seminal vesicles, and prostate deposits semen in the prostatic urethra, with α-sympathetic bladder-neck closure. Damage to these fibres (e.g. RPLND) causes retrograde ejaculation.
- Ejection — bulbar-urethral distension triggers the somatic pudendal nerve (S2–S4) → rhythmic bulbocavernosus contractions with external-sphincter relaxation → antegrade expulsion.
- Neurochemistry — dopamine (D2) promotes and serotonin inhibits ejaculation; PE is linked to 5-HT2C hyposensitivity / 5-HT1A hypersensitivity.
Distinguish retrograde ejaculation from failure of emission with a post-orgasm urinalysis (sperm in the urine = retrograde). In spinal-cord injury, ejaculatory ability improves with more caudal lesions (the opposite of erectile recovery).
Premature Ejaculation
The commonest male sexual dysfunction. The ISSM definition is ejaculation within ~1 minute (lifelong) or a bothersome fall to ~3 minutes (acquired), with an inability to delay and negative personal consequences. Subtypes are lifelong, acquired, variable, and subjective. Acquired PE is often driven by erectile dysfunction (treat the ED first), performance anxiety, prostatitis/CPPS, or hyperthyroidism.
Management is staged:
- First-line — psychosexual therapy (squeeze and stop-start techniques).
- Second-line — pharmacotherapy (mnemonic PASTA): PDE5 inhibitors (only with comorbid ED), topical Anaesthetic (lidocaine/prilocaine 20–30 min before, then wiped off), SSRIs (paroxetine has the strongest effect, ~8.8× IELT; daily or on-demand dapoxetine), Tramadol, and Alpha-blockers — all off-label.
Delayed Ejaculation and Anejaculation
Latency >25–30 minutes with distress, or absent ejaculation (lifelong in ~25%, acquired in ~75%). Causes:
- Neurogenic / surgical — radical prostatectomy (anejaculation but orgasm preserved), RPLND (anejaculation in non-nerve-sparing; antegrade preserved in 80–100% with nerve-sparing), proctocolectomy, and spinal-cord injury.
- Endocrine — diabetes, hypogonadism, hypothyroidism (strongly associated), and hyperprolactinaemia.
- Drugs — SSRIs, antipsychotics, tricyclics, α-methyldopa, and alcohol.
Management: psychosexual therapy, lifestyle change, and pharmacotherapy (pseudoephedrine, cabergoline, and others — generally low efficacy). For spinal-cord injury, vibratory stimulation and electroejaculation retrieve semen but risk autonomic dysreflexia.
Retrograde Ejaculation
Follows bladder-neck disruption — classically TURP — and diabetes. Diagnose with a post-ejaculate urine showing sperm. Treat with α-agonists (pseudoephedrine, ephedrine, midodrine) or imipramine to restore bladder-neck closure.
Painful Ejaculation and POIS
Painful ejaculation reflects an underlying cause (urethritis, BPH, prostatitis/CPPS, ejaculatory-duct obstruction) and is treated accordingly. Post-orgasmic illness syndrome (POIS) is a flu-like illness with myalgia and fatigue beginning within 30 minutes of orgasm — proposed to be a type 1 hypersensitivity reaction, sometimes treated with autologous-semen hyposensitisation.
Self-Test
1. What nerves and levels mediate emission vs ejection? Emission — sympathetic T10–L2 (with α-sympathetic bladder-neck closure); ejection — the somatic pudendal nerve, S2–S4.
2. How is retrograde ejaculation distinguished from failure of emission? A post-orgasm urinalysis shows sperm in the urine in retrograde ejaculation.
3. What is the ISSM definition of premature ejaculation? Ejaculation within ~1 minute (lifelong) or a bothersome reduction to ~3 minutes (acquired), with an inability to delay and negative personal consequences.
4. Outline PE management. Treat any ED first; first-line psychosexual therapy (squeeze, stop-start); second-line pharmacotherapy (PASTA — PDE5i if comorbid ED, topical anaesthetic, SSRIs [paroxetine strongest], tramadol, α-blockers).
5. What are the commonest causes of retrograde ejaculation, and its treatment? TURP and diabetes; α-agonists (pseudoephedrine, ephedrine, midodrine) or imipramine.
6. How does spinal-cord-injury level affect ejaculation versus erection? Ejaculatory ability improves with more caudal injuries — the opposite of erectile recovery, which is better preserved with higher (upper-cord) lesions.