476 CHAPTER 11 Infertility

Oligospermia and azoospermia

Oligospermia

Oligospermia is defined as a sperm concentration of <20 million/mL of ejaculate.

Etiology

It is often idiopathic. It is identified in ~60% of patients presenting with testicular cancer or lymphoma.

Associated disorders

It is often associated with abnormalities of morphology and motility (oligoasthenoteratospermia). Common causes include varicoceles, cryptorchidism, idiopathic, drug and toxin exposure, and febrile illness.

Investigations

Semen analysis: Severely low sperm counts (<5–10 million/mL) require hormone investigation, including FSH and testosterone. Severe oligospermia is associated with seminiferous tubular failure, small soft testes, and iFSH.

Treatment

Correct the underlying cause. Idiopathic cases may respond to empirical medical therapy. Clomiphene and tamoxifen are mild antiestrogens that work best for men with low to normal testosterone and FSH levels.

Consider assisted reproductive techniques, such as intrauterine insemination (IUI) or intracytoplasmic sperm injection (ICSI).

Azoospermia

This is defined as a complete absence of sperm in the ejaculate fluid.

Etiology

•Obstructive: absent or obstructed vas deferens; epididymal or ejaculatory duct obstruction. The cystic fibrosis gene is located on chromosome 7 and the condition is associated with congenital absence of the vas deferens (CAVD).

•Nonobstructive: hypogonadotrophism (Kallmann’s syndrome, pituitary tumour); abnormalities of spermatogenesis (chromosomal anomalies, toxins, idiopathic, varicocele, orchitis, testicular torsion)

Investigations

Hormone assay

Elevated FSH indicates a nonobstructive cause; normal FSH with normal testes indicates an increased likelihood of obstruction. Low levels of FSH, LH, and testosterone indicate Kallmann’s syndrome (hypogonadotropic hypogonadism) due to hypothalamic dysfunction and absence of GnRH secretion.

Prader-Willi syndrome also has absent GnRH secretion. It is associated with obesity, mental retardation, and short stature, whereas Kallman’s syndrome is associated with anosmia.

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Chromosomal analysis

This may be used to exclude Kleinfelter’s syndrome in patients presenting with azoospermia, small soft testes, gynecomastia, iFSH/LH, and dtestosterone.

Testicular biopsy

This is best performed as an open procedure. It is performed to assess if normal sperm maturation is occurring and for sperm retrieval (for later therapeutic use).

Diagnostic biopsy is indicated in azoospermic men with testes of normal size and consistency, palpable vasa deferentia, and normal FSH levels. Biospy may also be therapeutic, since sperm can be retrieved on testis biopsy from 25–50% of patients with Sertoli cell only syndrome, and 50–75% of men with maturation arrest. Multiple sample sites are performed if sperm are not immediately obtained.

Transrectal ultrasound

This is indicated for low semen volume to assess for ejaculatory duct obstruction. Men with ejaculatory duct obstruction will tend to have low semen volume and fructose, and semen pH <7.

Management

Treatment will depend on the underlying etiology.

•Transurethral resection of ejaculatory ducts (TURED) is associated with improved semen quality in 52%.

•Bilateral absence or agenesis of vas deferens: microsurgical epididymal sperm aspiration (MESA), or consider artificial insemination using donor (AID).

•Primary testicular failure with testicular atrophy: testicular sperm extraction (TESE); in vitro fertilization (IVF); or consider AID.

•Primary testicular failure with normal testis: TESE; IVF; AID

•Obstructive cause with normal testis: epididymovasostomy; vasovasostomy

478 CHAPTER 11 Infertility

Varicocele

Definition

Varicocele is dilatation of the veins of the pampiniform plexus of the spermatic cord.

Prevalence

This is the most common correctable cause of male infertility. Varicocele is found in 15% of men in the general population and 40% of males presenting with infertility. Bilateral or unilateral (left side affected in 90%).

Etiology

Incompetent values in the internal spermatic veins lead to retrograde blood flow, vessel dilatation, and tortuosity of the pampiniform plexus. The left internal spermatic vein enters the renal vein at a right angle, creating a column of blood that is under a higher pressure than that in the right vein, which enters the vena cava obliquely at a lower level. As a consequence, the left side is more likely to develop a varicocele.

Pathophysiology

Testicular venous drainage is via the pampiniform plexus, a meshwork of veins encircling the testicular arteries. This arrangement normally provides a countercurrent heat exchange mechanism that cools arterial blood as it reaches the testis. Varicoceles adversely affect this mechanism, resulting in elevated scrotal temperatures and consequent deleterious effects on spermatogenesis (± loss of testicular volume).

Varicocele grading system

Presentation

The majority of varicoceles are asymptomatic, although large varicoceles may cause pain or a heavy feeling in the scrotal area. Examine patient both lying and standing, and ask patient to perform Valsalva maneuver (strain down).

A varicocele is identified as a mass of dilated and tortuous veins above the testicle (described as feeling like a “bag of worms”), which decompress on lying supine. Examine for testicular atrophy, which is often associated with chronic testicular injury.

Investigation

•Scrotal Doppler ultrasound scan is diagnostic.

•Semen analysis: Varicoceles are associated with reduced sperm counts and motility, and abnormal morphology, either alone or in combination (oligoasthenoteratospermia).

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Management

Surgical ligation

•Retroperitoneal approach: A muscle-splitting incision is made near the anterior superior iliac spine, and the spermatic vessels are ligated at that level.

•Inguinal approach: The inguinal canal is incised to access the spermatic cord, and the veins are tied off as they exit the internal ring.

•Subinguinal approach: Veins are accessed and ligated via a small transverse incision below the external ring.

•Laparoscopic: Veins are occluded high in the retroperitoneum.

Surgical complications include varicocele recurrence, hydrocele formation, and testicular infarction and atrophy.

Surgical outcome

There is a 95% success rate; 70% of men have improvement of sperm parameters—most often motility, followed by count and then morphology. Testicular growth is often impaired in adolescents with varicoceles, but surgical repair may result in catch-up growth.

Embolization

In this interventional radiological technique, the femoral vein is used to access the spermatic vein for venography and embolization (with coils or other sclerosing agents).