Hypogonadism or below normal testosterone is a well recognized entity affecting a significant number of men. Symptoms can include low desire for sex or libido as well as low energy. Of course those symptoms can be ascribed to other conditions as well including, but not limited to depression or hypothyroidism; but for those men who truly have hypogonadism, treatment is readily accomplished with a variety of available agents. Where appropriate, raising testosterone levels back to normal can make a striking difference in the quality of a man’s life.
Why is low testosterone suddenly a new hot topic? Awareness about men with “Low T” or low testosterone has exploded practically overnight. The explanation for this is very simple: there are a number of new pharmaceutical agents available to treat it and the pharma industry has put resources to work, advertising for their products. “Low T” commercials abound. Talk shows feature the topic. Physicians have been writing books and or lecturing on the subject. As a result, the demand for evaluation and treatment has increased.
What happens to sperm production during testosterone replacement therapy? Most of the new products are actually delivery systems for testosterone which is, itself, a natural body hormone. The testes have two main functions: generation of sperm and generation of testosterone. The administration of exogenous (from outside the body) testosterone will cause the testicles to effectively take a break and reduce their production of both testosterone and sperm. Therefore, testosterone administration will eventually reduce sperm production. In some cases it can suppress sperm production completely and render the patient azoospermic (no sperm in the ejaculate). For most men, this is reversible; however, the longer testosterone administration is given the greater the risk with regards to getting sperm production to come back or at least to return to its prior levels.
So, what are the possible choices for men who begin Testosterone Replacement therapy, but want to maintain their options for future fertility?
1. Sperm banking (Cryopreservaton)
Cryopreservation of Sperm is typically thought of as an option for fertility preservation in the setting of cancer, prior to beginning chemotherapy; however, anytime therapy that threatens sperm production is going to be given, sperm banking can be utilized. Usually one or two ejaculated specimens is/are usually submitted. These specimens can remain frozen for years or even decades. Once the specimens are frozen, the patient can begin his therapy.
2. Using agents other than testosterone to treat hypogonadism
Certain medications such as SERMs (selective Estrogen Receptor Modifiers) or Aromatase inhibitors will cause testes to increase endogenous (the body’s) production of testosterone and therefore also maintain sperm production, so that exogenous testosterone is not needed. However, use of these medications for this purpose is considered off label and safety data is limited, particularly for prolonged use. Testosterone, by way of comparison, is a substance found naturally in the body and extensive testing has been performed regarding its use and the use of the newer delivery systems.
3. Use of a gonadatropic agent along with testosterone
In the body, the testes release testosterone and sperm in response to certain pituitary hormones called gonadatropins. Levels of those hormones drop when exogenous testosterone is administered and in response, the testicles slow down their function; in other words, the engine that drives the production of sperm slows or can even stop. Certain medications such as pregnyl, hmg, menopur and others mimic natural pituitary hormones. Administration of these agents along with Testosterone have the ability to keep the engine running. Again, use of these agents in this way is considered off label and limited safety data is available, particularly for long term use
4. Fix the underlying problem
This can be an alternative for some men who have an identifiable problem as a cause for low testosterone. Some causes for low T include the presence of a benign pituitary growth such as prolactinoma. This can often be addressed with medication. Some patients may have sleep apnea which can be treated in a variety of ways. Metabolic syndrome which is a constellation of findings including low testosterone and insulin resistance can be treated by weight loss. Clearly fixing an underlying problem would seem to be the most desirable way to treat hypogonadism, if it is an option.
A number of options exist for hypogonadal men who want to treat their low testosterone level but who also want to conceive a child or at least hold that option open in the future. It may be beneficial to consult with doctors who have additional training in the treatment of infertility when confronted with this situation, particularly if considering any option that involves the off label use of medication.