Azoospermia, the term which describes complete absence of sperm in the ejaculate, is a diagnosis most men dread. Often, this diagnosis is associated with the fact that possibility of ever fathering a child has been completely ruled out. In reality however, it is known that semen analysis which shows absence of sperm in the ejaculate does not always rule out the possibility of sperm production on one hand or non- delivery to the semen on the other. Neither does it rule out the fact that inventions may help the man produce sperm. Even in cases where after intervention there is still no sperm in the ejaculate, there is always a possibility of harvesting small amounts of sperm produced in the testes from any or all of the interventions.

When faced with Azoospermia, the primary question is usually whether the problem lies in sperm production or in its delivery. Are the testes simply not producing sperm or are they producing sperm but unable to deliver it in the ejaculate? An initial evaluation is often necessary to distinguish between two possibilities. Assuming the testes are producing sperm and none is detectable in the ejaculate, it is then a problem of delivery but the sperm can be retrieved one way or another, if it is established that sperm is not being produced it becomes necessary to explore what the problem is and how it can be resolved. A number of techniques utilized for such sperm harvesting in conjunction with advanced reproductive techniques abound.

Generally, the primary causes of male infertility are problems with sperm production or delivery. Impaired production or delivery may result from hormonal dysfunction, trauma or defect in the reproductive system and illness. A common cause includes Cryptorchidism (failure of testes to descend); ductal obstruction (sperm carrying duct may be missing or blocked). The blockage may be bilateral (both sides) or congenital (from birth), it may be a mechanical blockage arising from a hernia, hydrocele repair or from scar tissues as a response to an infection. Another cause of male infertility is hemochromatosis (a metabolic disorder that cause iron deposition in the testes); hormone dysfunction; retrograde ejaculation (impairment  of the muscles or nerves of the bladder neck prohibits during ejaculation, allowing semen to flow backward into the bladder); drugs ( certain drugs used to treat hypertension, arthritis, and digestive disease as well as chemotherapy drugs including antibodies can impair a sperm cell ability to swing through cervical mucus or to penetrate a female egg) and infection with STDs/STIs.
Others includes sickle cell anemia; testicular cancer or trauma resulting from injuries, surgery, or infection; systemic disease and inflammatory infection of the prostrate (prostatitis) epididymis (epididymitis) and testicles (orchitis) especially before puberty. Varicocele (a dilated vein in the scrotum which allows extra blood to pool in the scrotum, it is the most common reversible cause of male factor infertility) and abnormalities in the seminal fluid impairs sperm movement into the female reproductive tract.

One major causative factor for lack of sperm production is traceable to hormonal problems. Normally, the testicles may be supplied with hormones from the pituitary gland in order to be stimulated to make sperm. Absence or severe depletion of these hormones leads to impaired production. Uncontrolled intake of substances containing steroid for body building purposes generally minimizes production or hormones essential for sperm production. Inability of sperm producing part of the testicles to produce adequate numbers of mature sperm is a genetic abnormality referred to as testicular failure. The condition may occur at any stage in sperm production either because the testicles completely lack the essential sperm producing cells (sertoli cell-only syndrome) or due to inability of sperm to develop completely (maturation arrest). A third major azoospermia is attributable to varicocele development. Varicoceles are swollen veins in the scrotum which allows extra blood into the scrotum- a condition which has a negative effect on sperm production.

Sperm delivery complications are generally caused either by a problem with the ductal system that carries the sperm, or problems ejaculation. The sperm carrying duct nay be missing or blocked, in effect, the sperm which are stored in sacs called the seminal vesicles, cannot be deposited through the urethra as a result of factors ranging from neurological damage, diabetes or spinal cord injury amongst others. Also, for the sperm to be pushed out the tip of the penis, the entry to the bladder must be closed down. If it does not close down, the sperm will be push into the bladder and later washed out during urination.
In evaluating Azoospermia, evidence of severe diminution and present of dilated veins on the scrotum, is often an indication abnormality, also, absence of ductal system confirms a condition known as congenital bilateral absence of the vas deferens, (CBAVD). In most cases, this is considered to be due to the patient genetic make up and requires chromosomal analysis as part of the evaluation and treatment.

Role Played By Smoking
Cigarette smoking has shown significantly affect semen quality. Regular smoking actually causes a 23% decrease in sperm density (concentration) and 13% decrease in mortality (averages taken from nine separate studies).

To a lesser extent, smoking causes an increased number of sperm with abnormal morphology (shape). Smoking causes toxicity to seminal plasma (the fluid ejaculated with the sperm): sperm from non smokers were adversely affected (had significantly decreased viability) when placed in the seminal plasma (hormal) of smokers. Smoking affects the hypothalamic-pituitary- gonadtropin axis, most common affecting levels of estradiol and estrone (estrogens, which are hormones found in higher concentration in women).

The Leydig cells, which are in the testes and produces testosterone, may have secretary dysfunction.

Most worrisome is that there is evidence which suggests that paternal smoking may also be association with congenital anomalies and childhood cancer, though the relatively risk in most studies is less than two.