Retrograde Ejaculation Due to Posterior Urethral Stricture: A Rare Case Report

Abstract

Pelvic fracture is a serious injury, which has a profound impact on sexual function due to concurrent nervous and urethral injuries. In this case report, we describe a 29-year-old single man who had retrograde ejaculation as a result of a pelvic fracture-related posterior urethral stricture. The patient wanted to improve his ejaculatory ability after experiencing urethral stricture for 8 years and retrograde ejaculation for 3 years following the pelvic fracture. We precisely located and measured the patient’s urethral stricture using a retrograde urethrogram, and we used transrectal color Doppler ultrasound to track the patient’s ejaculation process in real time. Next, we used urethral balloon dilatation to relieve the urethral stricture. Urinary obstruction symptoms have completely resolved, and the patient was able to urinate without any obstructions. Meanwhile, the real-time transrectal color Doppler ultrasound result showed that some semen might ejaculate externally by passing through the initial stricture area, while some semen continued to flow retrogradely into the bladder.

Introduction

Normal ejaculatory and erectile functions are required for male reproduction to promote the transfer of semen. The most important aspect of sexual behavior and the pinnacle of male sexual behavior is ejaculation. Orgasm is a completely cerebral activity, but ejaculation is a different process that typically occurs simultaneously. Three physiological processes are involved in a normal male ejaculation: spermiation, ejaculation, and closure of the urethral orifice. The ejaculation is the act of forcing semen through the urethra and involves the coordinated action of several structures, including the prostate, ejaculatory ducts, seminal vesicles, epididymis, and vas deferens(Soni et al., 2022).

The prostatic, bladder neck and membranous urethras make up the posterior urethra. With a 10% occurrence rate, the main causes of posterior urethral strictures are traffic accidents, falls, or severe pelvic compression that results in pelvic fracture urethral damage(Bjurlin et al., 2009). The degree of urethral injury and the emergency management techniques are associated with posterior urethral strictures, which are consequences of urethral injuries following pelvic fractures. The distal portion of the membranous urethra is where adult injuries and strictures most frequently occur. Right now, urethral dilatation is still one of the most widely utilized therapeutic approaches.

The whole or partial rearward passage of semen into the bladder during ejaculation is referred to as retrograde ejaculation. Clinically, it is indicated by decreased ejaculate volume or non-existence of ejaculate at the urethral orifice following climax. Urine may appear turbid in certain patients following climax. One of the causes of male infertility is retrograde ejaculation(Gupta et al., 2022). In this study, we describe a man whose posterior urethral stricture caused retrograde ejaculation. After transurethral balloon dilation, his ejaculation function was recovered.

Case Report

A 29-year-old man who was single and had a sexual partner came to the hospital because he had been experiencing urethral stricture for 8 years and retrograde ejaculation for 3 years. The patient had no prior urinary issues or ejaculatory abnormalities, but experienced urinary obstruction after a non-surgically treated pelvic fracture 8 years ago, presenting with delayed and weak urination, thin urine stream, prolonged urination time, dribbling, incomplete bladder emptying, nocturia 1 to 2 times, and normal ejaculation. He started having weak ejaculations and decreased semen volume 3 years ago. After about 3 months, he had an orgasm and ejaculated normally, but no semen came out during sexual activity. Urinating for the first time after ejaculation initially showed rather white, murky urine. A digital rectal examination showed that the prostate had a shallow median sulcus, firm texture, and grade ã enlargement. No anomalies in the external genitalia were found. The anterior urethra was well visualized on a retrograde urethrogram (conducted by external urethral meatus injection of contrast agent) and did not narrow. However, the stricture was seen at the level of the posterior aspect of the symphysis pubis (Figure 1). Color of genitourinary system ultrasound Doppler showed that the prostate had dimensions of 49 × 36 × 26 mm and a 100 ml leftover urine capacity. The seminal vesicles’ MRI evaluation revealed no notable abnormalities because neither ejaculatory duct dilatation nor internal tubule of seminal vesicle dilatation was observed, and both seminal vesicles were full and symmetrical. Cystoscopy showed that the scope’s insertion failed at a distance of roughly 14 to 16 cm from the external urethral meatus because it was unable to fit through the posterior urethra’s narrowing. Transrectal color Doppler ultrasonography, which monitors ejaculation in real time by placing the ultrasonography probe in the rectum while the patient masturbates, showed that seminal fluid was obstructed at the narrowed posterior urethra during ejaculation, causing retrograde flow into the bladder (Figure 2a, Supplemental Video 1).

Figure 1.

Retrograde Urethrogram

Figure 2.

Transrectal Color Doppler Ultrasound

We created a transurethral ureteroscopy treatment plan for the patient (normal cystoscope or resectoscope cannot pass through urethral stricture). The urethra significantly narrowed, with a diameter of around 2 mm at its narrowest point, at a distance of 14 to 16 cm from the external urethral meatus, as indicated by the use of a pediatric narrow ureteroscope (6/7.5, WOLF, Germany). The narrowing extended to the bladder, and neither the bladder nor its neck showed any anomalies. The urethra was dilated by balloon dilation, which involved inserting an ultra-smooth guide wire and passing a balloon dilator (24F/30F, COOK, Germany) along the guide wire during the ureteroscope. Water was pumped into the balloon to keep the pressure at 20 mmH₂O for 2 min. A ureteroscopy performed later showed that the posterior urethral constriction had fully dilated. For a duration of 1 week, a 20F urinary catheter was inserted to widen the urethra. When the catheter was taken out a week later, the patient’s urinary obstruction symptoms had completely resolved and there was no longer any restriction to their urine. Transrectal color Doppler ultrasonography was used to track ejaculation dynamically in real time. The result showed that about 3 ml of semen ejaculated externally by passing through the initial stricture area, while some semen continued to flow retrogradely into the bladder (Figure 2b, Supplemental Video 2).

Discussion

The release of semen into the posterior urethra, the closure of the urethral opening (bladder neck), and the forward ejaculation of semen from the posterior urethra constitute the physiological process of proper ejaculation. The urethral sphincter contracts simultaneously to stop urine from entering the urethra during ejaculation and to stop semen from retrogradely entering the bladder when the ejaculated semen stimulates the prostatic urethra. This process is known as reflex closure of the bladder neck. Consequently, obstruction of the urethra, blocking of the sympathetic nerves in the inferior urinary system, or interference with the structural function of the bladder neck can all result in obstruction of semen discharge and retrograde ejaculation(Fedder et al., 2021).

Pelvic fractures make up approximately 3% of all skeletal injuries. Furthermore, 2% of men with traumatic pelvic fracture have a concurrent pelvic fracture urethral injury(Johnsen et al., 2017; Schulman et al., 2010). Pelvic fracture urethral injury describes posterior urethral damage caused by blunt force or high-energy trauma is associated with unstable pelvic fractures. The mechanism of injury is thought to be shearing and stretching forces that damage the surrounding puboprostatic ligaments and attachments of the membranous urethra(Kassiri et al., 2023). Mazzone et al. reported important sexual dysfunction metrics using the MSQH and non-validated questionnaires, which demonstrated pelvic fracture urethral injury patients have high rates of ejaculatory dysfunction including retrograde ejaculation(Mazzone et al., 2021). Retrograde ejaculation occurs in 1%-4% of males, which is not a typical occurrence in clinical practice. It accounts for 0.3% to 2.0% of the infertile population and is one of the reasons for male infertility (Fedder et al., 2021). Retrograde ejaculation is a major cause of azoospermia, even though it does not account for a considerable fraction of the infertile population. The following 5 elements are the primary etiological determinants of retrograde ejaculation: (a) Bladder neck disorders: these include broad bladder necks that are hereditary and surgically injured necks that might cause inadequate neck closure and retrograde ejaculation; (b) Urethral disorders: urethral valve syndrome, urethral stricture caused by trauma or inflammation, can increase urethral resistance, leading to obstruction of semen during ejaculation causing retrograde ejaculation; (c) Neurological disorders: congenital spina bifida, spinal cord injury, diabetes causing autonomic neuropathy affecting bladder neck closure(Hylmarova et al., 2020, p. 4) Drug effects: alpha-adrenergic blockers (e.g., silodosin), antihypertensive drugs (e.g., prazosin), antiepileptic drugs (e.g., phenytoin sodium), antipsychotic drugs (e.g., risperidone), these medications can reduce sympathetic nervous system excitability, interfere with sympathetic nerve impulses governing the bladder neck, and affect the contraction of the urethral sphincter muscle, causing semen to flow backward into the bladder resulting in retrograde ejaculation (Salonia et al., 2021, p. 5). Endocrine factors, hypothyroidism, may present with mononeuropathy and sensorimotor polyneuropathy if involving ejaculation control nerves, it can lead to retrograde ejaculation; hyperprolactinemia can inhibit the metabolism of dopamine, a precursor of adrenergic receptor agonists, causing incomplete closure of the bladder neck, thereby leading to retrograde ejaculation(Haefliger & Bonsack, 2006; Komiya et al., 2012). The confirmation of the diagnosis of retrograde ejaculation can be obtained from the patient’s medical history and description, as well as from a urine examination performed right after ejaculation, which might show a significant amount of sperm in the urine. The diagnosis can also be aided by neurophysiological testing, bladder neck examination, urethra imaging, and cystography. When facilities allow it, transrectal ultrasound can be used to further confirm the diagnosis by providing real-time dynamic monitoring of the ejaculation process. Retrograde ejaculation does not have a specific treatment at this time. There are some therapeutic benefits to medication therapy and bladder neck restoration, but the results are not conclusive. Sperm obtained from urine can usually be used for assisted reproductive methods for fertility purposes.

Only 40% of men with ejaculatory dysfunction after posterior urethroplasty compared to 60% after pelvic fracture urethral injury. Pre-urethroplasty the mechanism could be explained by the complete obliteration of the posterior urethra(Mazzone et al., 2021). In this case report, retrograde ejaculation, which is uncommon in clinical practice, caused by posterior urethral stricture is taken into consideration. The patient did not use any medications that would have affected bladder neck function at first, and he had normal sympathetic nerve function controlling bladder neck closure. The posterior urethra was injured following a severe pelvic fracture, which resulted in posterior urethral stricture. Furthermore, it was possible that the fracture fragments altered the bladder neck’s structure, impairing the function of the bladder neck closure. Due to increased voiding pressure caused by the posterior urethral stricture, the patient had to urinate for a longer period, which may have overcompensated the bladder sphincter muscle. This explained why the patient originally had trouble peeing following urethral stricture and then developed ejaculation dysfunction later. The function of the bladder neck gradually reduces with time, causing the bladder neck to become less taut and lose its capacity to contract. This resulted in insufficient bladder neck closure, which in turn caused retrograde ejaculation.

To determine the precise location and extent of the patient’s urethral stricture, we first used a retrograde urethrogram. Next, we used transrectal color Doppler ultrasound to monitor the patient’s ejaculation process in real time and to identify the specific circumstances and causes of retrograde ejaculation, which was the novelty of this case. Finally, we used urethral balloon dilatation to treat the urethral stricture, which helped the patient’s retrograde ejaculation and alleviated the voiding problems. In this case, we hope to shed light on how similar patients should be managed. To assess the efficacy of this strategy, additional observations on more cases are necessary.

There are still some constraints to this case report. The patient’s follow-up time is only a few months, and longer follow-up should be recommended.

Conclusion

We describe a man who had retrograde ejaculation as a result of posterior urethral stricture. After transurethral balloon dilation, ejaculation function was restored, indicating that our treatment is effective in restoring patient ejaculatory function and can result in a clinically significant improvement in such patients.