Around 300 million male germ cells are sent on their way with each ejaculation, and they have only one goal: to find the egg cell and fertilize it. But only one sperm will reach its destination – or it won’t. Because not every man is biologically fertile. According to studies, the consumption of cannabis and other drug-related habits could be a reason for the hormonal balance in men being permanently upset and infertility as a consequence.
Male infertility is now a problem for many unintentionally childless couples. An American research team and treatment facilities like Addiction Treatment Phoenix AZ have investigated the question of how illegal drugs can affect male fertility.
THC curbs testosterone
Due to its widespread use, cannabis is of great importance when it comes to male fertility. In the body, THC, the main active ingredient in cannabis, attaches to the same receptors that are occupied by the body’s own substances, the endocannabinoids. It is known that endocannabinoids play an important role in reproduction. Endocannabinoid receptors are found in the testes, among other places, and are involved in controlling sperm production there. There are even receptors for endocannabinoids in the sperm itself.
When smoking weed, THC not only gets into the brain but is also transported via the bloodstream to the testicles, where it binds to the corresponding receptors and thus can disrupt the so-called hypothalamus-pituitary-testicle axis. The hypothalamus and the pituitary gland are two structures in the human brain that work together with the testes to regulate the production of the sex hormone testosterone. One guess is that if THC binds to the receptors in the testicles, it could reduce testosterone production. Testosterone plays a central role in sperm production.
Studies show that testosterone level in the blood of chronic cannabis users was significantly lower than that of abstinent control persons. In addition, the testosterone level was dependent on the amount consumed: the more the subjects smoked, the less testosterone they had in their blood. The decreased production of testosterone, in turn, presumably had greatly reduced the number of sperm in the stoner’s ejaculate. This so-called oligospermia was detected in over a third of the chronic cannabis users examined.
Impaired sperm quality
However, not only does the number of sperm cells decrease but also their quality. As further studies have shown, THC also restricts the sperm’s ability to move. This could be due to the fact that THC promotes so-called programmed cell death (apoptosis). A large proportion of immobile sperm is then found in the ejaculate.
The negative influence of THC may also be exacerbated by its relatively long-term availability in the body. Normally, the body’s own endocannabinoids are made available quickly as needed and broken down again just as quickly. When smoking weed, however, the body is literally flooded with THC. The plant cannabinoid is also stored in adipose tissue and gradually released from there. Such “THC reservoirs” in the testes could overstimulate the cannabinoid receptors there and have the negative consequences described for the quality of the sperm.
Ecstasy & Speed: Damage to DNA
Similar to cannabis, ecstasy and speed also impair the normal activity of the hypothalamus-pituitary-testis axis and thus also the production of testosterone. So far, however, the effects of amphetamines have only been investigated in animal studies. In one experiment, male rats were given ecstasy in an amount that is said to correspond approximately to the amount of recreational consumption in humans. The rats’ testosterone levels were then reduced by 50 percent.
More detailed studies of the effects of ecstasy on the testes and the quality of the sperm cells of rats also showed significantly more frequent damage to the genetic material (DNA) contained in the sperm and to the testicular tubules in which the sperm are produced. Unlike THC, however, ecstasy did not lead to reduced mobility or other external abnormalities of the sperm.
Cocaine: degenerate cells
As with amphetamines, most of the knowledge about the effects of cocaine on male fertility comes from animal studies. Rats that were given cocaine for several months in the experiment had about half the probability of producing offspring compared to their abstinent conspecifics. In order to find out the reasons for these differences, these test animals were also examined in detail after the end of the experiment.
Researchers found degenerate and abnormal cells in the sperm-producing testicular tubules of the test animals treated with cocaine. In both high and low doses, cocaine had acute negative effects on sperm production. High doses of cocaine also impaired the blood supply to the testicles for several hours. This reduced blood flow could also partly explain the negative effects of cocaine on fertility.
A team of experts was able to show a large number of studies that have shown a negative influence of drug consumption on sperm production and sperm quality. However, it remains unclear in how many cases substance abuse actually plays a relevant role in existing male infertility. According to the Robert Koch Institute, around 5 to 10 percent of couples in Germany are currently involuntarily childless, and around 3 percent have a long-term unfulfilled desire to have children.