Research reveals methamphetamine's severe impact on male fertility

Researchers at the University of the Western Cape (UWC), in a groundbreaking study, have found that methamphetamine, commonly known as tik in South Africa, can seriously harm male fertility, even after short-term use.

Researchers at the Department of Medical Bioscience have discovered that tik damages key testicular cells responsible for sperm production. The study, led by Prof David Fisher and his team, focused on Sertoli cells, which play a critical role in nurturing developing sperm in the testicles.

They also found that both occasional and long-term use of methamphetamine can harm these cells, potentially leading to a drop in sperm count and quality. Prof Fisher said his team’s research found that tik’s harmful effects on male fertility occur within 24 hours of use and some long-term effects over 96 hours. The study looked at casual users, who might consume the drugs on weekends and those who use the drug almost, if not, every day.

Sertoli cells act like 'nurses' to sperm-producing cells.They provide essential nutrients and help form a barrier - the blood-testis barrier - that protects sperm from toxins and immune system attacks. When these cells are damaged or weakened, sperm development suffers.

“Sertoli cells are absolutely essential for sperm production,” explained Dr Fisher. “If these cells are not healthy, men will struggle to make healthy sperm.”

Prof Fisher explained that Sertoli cells regenerate daily, meaning they have the ability to divide and potentially recover. “Any cell capable of division can recuperate. In contrast, long-term cells like spermatogonia—which we haven’t yet studied directly—may be more vulnerable. If tik affects these stem cells, as we suspect it does, it could lead to a reduction in their numbers. This, in turn, would decrease the stem cell pool responsible for producing sperm,” he said.

In cases of long-term exposure, the damage is much worse. The Sertoli cells stopped dividing as they should, their energy levels dropped, and their ability to protect developing sperm was reduced. These effects were most pronounced at higher drug concentrations, which are similar to levels found in heavy tik users.

“In the long run, methamphetamine causes Sertoli cells to become less active and less able to perform their job,” said Dr Fisher. “This can result in fewer sperm being made and more of them being abnormal.”

One of the most concerning discoveries is how Tik weakens the blood-testis barrier. This barrier is vital for keeping harmful substances away from sperm during development. After tik exposure, this barrier becomes “leaky” and may allow toxins to reach developing sperm cells, further harming fertility.

In recreational users, the damage to the barrier was temporary but still noticeable. However, the barrier was consistently weakened in long-term users throughout the study period. Prof Fisher said that, looking at pathology, the testes of tik users were also smaller than those of other males. Compared to alcohol’s and cannabis’ effect on male fertility, Prof Fisher said alcohol has a detrimental impact, but not as bad as tik. He said his team will next look at the “blood/brain barrier” effect of tik and whether this could lead to increased incidents of strokes within users.

“We have also seen that the endothelium cells of the capillaries in the brain stop growing; they stop dividing. And if we now look at the pathology of tik in the world, we find out that the incidence of hemorrhagic stroke in young tik users is at an all-time high,” said Prof Fisher.

Dr Chontrelle Willemse, one of the researchers involved in the study, emphasised that overcoming a tik addiction ultimately comes down to making significant lifestyle changes. She added that support from family or the broader community is often essential in helping individuals move toward a healthier, more stable life.

This was a laboratory study, meaning the research was done on cells in a controlled environment, not on people. However, the results line up with other studies done on animals and humans that show methamphetamine lowers sperm count and damages testicular tissue.

The researchers hope to build on this pilot study by examining how tik affects entire testicular systems and to explore possible treatments to reverse or protect against the damage.

The study’s message is clear: methamphetamine isn’t just a threat to your brain and heart—it’s a threat to your future family. While South Africa continues to battle tik addiction, this UWC research provides yet another reason to avoid the drug.

“You’re not just risking your health,” said Dr Fisher. “You could be risking your ability to ever have children.”