Azoospermia (commonly referred to as “no sperm count”) is a male fertility issue many men face. Azoospermia is defined as the complete lack of sperm in the ejaculate. It occurs in 5% of infertile men. If this is the case, then one or both of two conditions may be present:
One important point concerning this diagnosis is that although no sperm are found in the ejaculate, there are often usable sperm found in the testis, as not all sperm that are made in the testis actually make it into the ejaculate. There is a “threshold” effect with sperm production, such that if production of sperm is high enough in the testis, then sperm “spill over” into the ejaculate. However, if that critical level of sperm production is not met, there may still be mature sperm in the testis that do not make it into the ejaculate. This concept is the basis for the statement that “sterility may beget fertility".
First, a thorough review of medical problems, exposures, past surgery, medications, and family history is undertaken in the office to help define causes of azoospermia. Then, a brief, well-performed physical examination is performed. Third, blood tests are taken that include testosterone and follicle stimulating hormone (FSH). Fourth, two semen samples are needed. With each sample, a standard semen analysis is performed. If no sperm are found, then the semen sample undergoes an additional evaluation in which the sample is “spun” down in a centrifuge to concentrate small numbers of sperm at the bottom of the tube. This “pellet” of the ejaculate is then examined thoroughly for sperm by an experienced lab technician. If 10 sperm or even 1 sperm is present in the pellet analysis, then conditions such as reproductive tract obstruction are painlessly disproved.
Again, the value of finding even a small number of sperm in the pellet analysis is very significant because:
If, based on the above evaluation, it is not entirely clear as to whether there is a problem with sperm production or one of a blockage in the ducts of the reproductive tract, then the next step is to examine the testis itself and assess sperm production. This can be done in several ways, but the classic approach is to perform a testis biopsy under local anesthesia.
Causes for Azoospermia
Conditions that cause azoospermia are listed in Table 1. If at all possible, treating the specific condition that is causing the azoospermia may reverse the process and lead to sperm production. This is especially true for azoospermia due to hot tubs or hot baths or testosterone supplements. In other cases, such as genetic infertility, this is not possible and assisted reproduction offers the best solution to family building.
Azoospermia due to Blockage
Clinically, it is important to determine whether men with azoospermia have an obstruction as a cause of the problem as this can be treated and reversed with microsurgery. If sperm production is normal, as determined by a testis biopsy or FNA mapping, then the azoospermia is caused by an obstruction. Typically, in an obstructed man without an obvious reason for the problem, a blockage can be found in the epididymis 65% of the time, in the vas deferens 30% of the time and in the ejaculatory duct 5% of the time. The actual location of the blockage can be pinpointed with microsurgery, and microsurgery repair has superb success rates for achieving moving sperm in the ejaculate and pregnancy in cases of blockages in the epididymis (the most difficult area to repair in the system) not due to vasectomy.
Azoospermia Without Obstruction
In cases of nonobstructive azoospermia in which sperm production is not normal, then it is assumed that obstruction does not exist. In a few cases, this condition is medically treatable (Kallman syndrome, hyperprolactinemia); in most instances however, the only hope for building a biological family is to use sperm retrieved from the testis with assisted reproduction in the form of IVF and ICSI. One of the most difficult aspects of nonobstructive azoospermia, is that while testis sperm retrieval in men with obstruction is not difficult, there is a failure to obtain sperm for ICSI in up to 50% of men with nonobstructive azoospermia. In addition, recognized clinical features like testicular size, history of ejaculated sperm, serum FSH level, or biopsy reading, do not accurately predict whether or not sperm will be recovered from the testis.
Currently, several strategies are used to find sperm in these men and to minimize trauma to the testis during sperm harvest.
If sperm are not found in the ejaculate, then there is either obstruction or blockage in the reproductive tract or sperm is not being made at levels sufficient to get into the ejaculate. A blockage can be due to prior infection, surgery, prostatic cysts, injury or congenital absence of the vas deferens (CAVD). Except for cases of congenital absence, most cases are of obstruction are repairable with microsurgical or endoscopic reconstruction.
In cases of azoospermia that is not due to blockage, termed nonobstructive azoospermia, medical treatment can help some men develop ejaculated sperm (i.e. those with reversible conditions such as Kallman syndrome, hyperprolactinemia; varicocele); in most instances however, the only hope for building a biological family is to use sperm retrieved from the testis with assisted reproduction. One of the most difficult aspects of nonobstructive azoospermia is that only 50%-60% of men will have usable testicular sperm. In addition, recognized clinical features like testicular size, history of ejaculated sperm, serum FSH level, or biopsy reading, do not accurately predict whether or not sperm will be recovered from the testis. Alternatively, patients with blockage can undergo sperm retrieval and use assisted reproductive technology to conceive. Please bear in mind that the use of assisted reproduction is the more expensive option of the two in general and involves conceiving in the laboratory and not in the comfort of your own home.