Absence of sperm at ejaculation

Emobileclinic Trending Topic: Azoospermia

Azoospermia is the medical term for a condition in which no measurable amount of sperm is present in a male’s semen. Put simply, it the absence of sperm in the ejaculate, is identified in approximately 1% of all men and in 10 to 15% of infertile males.  Most patients assume that this diagnosis would rule out the possibility of his ever conceiving a child; if there are no sperm how can there be conception?

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In the past, men with azoospermia were classified as infertile, and a sperm donor was initially considered one of the best options for conceiving. Currently, the knowledge that many causes of azoospermia can be reversed is widespread in the medical literature and practice. Thus, any trusted specialized assisted reproductive center will request a urologist/andrologist to provide sperm for an assisted reproductive technology procedure. 

Types

There are two types of azoospermia:

Obstructive azoospermia: refers to problems in sperm transport from the testis to the penis

Non-obstructive azoospermia: refers to defects in sperm production. 

As a result of the lack of sperm in the ejaculate, azoospermia results in infertility and sterility. However, depending on the type of azoospermia, certain assisted reproductive technology procedures, such as TESE and ICSI, can be used to help a man affected by this condition conceive a child.

Diagnosis of Azoospermia

The diagnosis is confirmed by centrifugation of a semen specimen for 15 min at room temperature with high-powered microscopic examination of the pellet and a centrifugation speed of at least 3,000 g. The semen analysis should be performed according to the 2010 World Health Organization guidelines, and at least two semen samples obtained more than two weeks apart should be examined.

Causes of azoospermia

The three major causes for lack of sperm production are hormonal problems, testicular failure, and varicocele.

Hormonal problems: the testicles need pituitary hormones to be stimulated to make sperm. If these are absent or severely decreased, the testes will not maximally produce sperm. Importantly, men who take androgens (steroids) either by mouth or injection for body building shut down the production of hormones for sperm production.

Testicular failure: the inability of the sperm producing part of the testicle (the seminiferous epithelium) to make adequate numbers of mature sperm. This failure may occur at any stage in sperm production for a number of reasons. Either the testicle may completely lack the cells that divide to become sperm (this is called “Sertoli cell-only syndrome.”) or there may be an inability of the sperm to complete their development (this is termed a “maturation arrest.”) This situation may be caused by genetic abnormalities, which must be screened for.

Varicocele: A varicocele is dilated veins in the scrotum, (just as an individual may have vericose veins in their legs.) These veins are dilated because the blood does not drain properly from them. These dilated veins allow extra blood to pool in the scrotum, which has a negative effect on sperm production. This condition may be corrected by minor out-patient surgery.

Evaluation of Azospermia

This can be done in the following ways:

Physical Examination

The simplest test is the physical examination. Since the bulk of the testes is comprised of the sperm producing elements, (the seminiferous epithelium), if the size of the testicles is severely diminished, this is an indication that the seminiferous epithelium is affected. Follow up hormonal profiles can determine whether this is a primary problem or caused by inadequate hormonal stimulation.

The scrotum is examined for the presence of dilated veins (varicocele). Their presence can be confirmed by an ultrasound probe placed on the skin at the scrotum.

During a physical examination, the ductal systems can be felt. If they are absent, the patient has what is called congenital bilateral absence of the vas deferens, (CBAVD). In most cases this is considered to be due to the patient’s genetic make-up and requires chromosomal analysis as part of the evaluation and treatment.

Finally, during examination of the ductal structures, the epididymis may feel as though it is dilated. Generally, it is flat and the middle cannot be felt. Thus, a dilated epididymis may be indicative of a blockage.

Hormonal Evaluation

Follicle stimulating hormone (FSH) is the hormone made by the pituitary, which is responsible for stimulating the testes to make sperm. When the sperm producing capacity of the testes is diminished, the pituitary makes more FSH in an attempt to make the testes do its job. Therefore, if a man’s FSH is significantly elevated there is a strong indication that his testicles are not producing sperm optimally. (Testosterone polactin, leutenizing hormone (LH) and thyroid stimulating hormone (TSH) are also measured to assess a man’s hormonal status. These may reveal problems that can significantly impact sperm production).

Genetic Testing: This is an area of active research. At this point it is recommended that all men receive basic genetic testing, measuring the number of chromosomes and looking at the blocks of genetic material. Screening for the genes that can cause cystic fibrosis is sometimes suggested. There are tests for specific genetic abnormalities on the male chromosomes that can cause azoospermia. If a son were to inherit this, he may have the same problem.

Transrectal Ultrasound

In order to rule out a blockage of the ejaculatory duct, an ultrasound of the ejaculatory duct and seminal vesicles is often performed. In this test the ultrasound probe is placed in the rectum since the ducts lie near its wall. Also, the ejaculatory duct traverses the prostate, a gland which can be felt through a man’s rectal wall. If the seminal vesicles are dilated, this indicates that they may be full of semen because they cannot empty properly. Cysts blocking the ejaculatory ducts by exerting pressure on their walls, or calcifications in the ejaculatory ducts themselves, may also be noted. A cyst in some cases may be unroofed by operating through the urethra to open it thus decompressing the ejaculatory duct. If the blockage occurs within the ejaculatory duct, the blocked part may be removed in a similar operation.

In conclusion, men facing a semen analysis fear the diagnosis of azoospermia. It is important to know that the diagnosis does not necessarily mean that the man produces no sperm or can never be made to produce any sperm and thus will never have a biological child. It is open to treatment, just that correctible causes must be found. In cases of absence of sperm in the ejaculate, sperm can often be aspirated to achieve fertilization.

 



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