Sperm production abnormalities
Chromosomal or genetic causes
Undescended testes
Infection
Testicle torsion
Varicocele
Radiation damage
Other unknown causes
Blockage of sperm ejaculate
Infection
Prostatic disease
Absence of vas deferens
Vasectomy
Abnormal erections and ejaculate
Retrograde or premature ejaculation
Absence of ejaculation
Erectile dysfunction
Spinal cord injury
Absence of intercourse
Prostatic surgery with damaged nerves
Specific medicines
Hormonal diseases
Pituitary neoplasm
Congenital lack of leuteinizing hormone/follicle-stimulating hormone
Androgenic steroid abuse
Sperm antibodies
Vasectomy
Infection of epididymis
Unknown causes
Semen Analysis
A laboratory analysis of semen determines the number of sperm and discovers abnormalities in the (morphology) and (motility) of the spermatozoids. The lab analysis of semen can also detect signs or problems such as infections.
Spermatozoids counts can fluctuate significantly, so in most cases, several semen analysis tests are done over a period of 1 year. The low number of spermatozoids occurs when the count is fewer than 15 million sperm per milliliter of semen or a total sperm count of less than 39 million per ejaculate [2, 3].
Hormone Testing
Testosterone is an androgenic hormone that is responsible for the development of the external male genitalia and secondary sexual characteristics. Most of this important hormone is secreted by the testicular Leydig cells and a minor part of this hormone is secreted by the adrenal cortex. Normal adult testosterone values range from 250 to 1100 ng/dL, with levels dropping slowly after age 30 [1, 2].
Post-ejaculation Urinalysis
The presence of spermatozoids in urine can indicate that sperm is going backward into the bladder instead of out of the penis during ejaculation; this is called retrograde ejaculation [1].
Genetic Tests
Testicular Biopsy
This procedure involves removing samples from the testicle with a needle. Whenever the results of testicular biopsy show that sperm production is normal, the infertility is likely caused by a blockage or another problem with sperm delivery; however, this sort of examination is not often used to diagnose the cause of infertility [1, 3].
Scrotal Ultrasound
This examination uses high-frequency sound waves to produce anatomical images. A scrotal ultrasound can help detect scrotal abnormalities such as varicocele, hypogonadism, post-torsion, epididymal cysts, absent epididymis, and tumors.
Nonobstructive Diseases of the Testes
Varicocele
Varicocele is caused by a dilatation of the pampiniform venous plexus and the internal spermatic vein. Clinically, varicoceles present a palpable, soft scrotal mass. Sometimes they are associated with moderate pain. Varicocele usually decreases testicular function; it occurs in approximately 15–20% of all males and in 40% of infertile males. Ultrasound examination is an excellent means of evaluating the pampiniform venous plexus, and with color Doppler it is possible to detect venous reflux during a Valsalva maneuver even in subclinical varicoceles [4–6].
Ultrasound B-mode shows tortuous, tubular, anechoic structures adjacent to the superior part of the testis and then correspond to dilated veins of the pampiniform plexus with calibers more than 2–3 mm during the Valsalva maneuver in the orthostatic position. Color Doppler ultrasound shows reflux into the pampiniform venous plexus and in the spermatic vein that increases during the Valsalva maneuver and can also be classified [4–7] (Figs. 10.1, 10.2, 10.3, and 10.4).
Fig. 10.1
Varicocele Grade 1. (a) No dilated intrascrotal veins. (b) Presence of reflux in the spermatic cord veins only during Valsalva maneuver
Fig. 10.2
Varicocele Grade 2. (a) B-mode shows dilated veins in the upper pole of the testicle. (b) Color Doppler shows reflux in the pampinform vein during Valsalva
Fig. 10.3
Varicocele Grade 3. (a) B mode ultrasound shows enlarged veins in the upper pole and in front of the testicle only in standing position. (b) Color Doppler shows reflux in the pampinform vein during Valsalva
