Male testosterone levels halve in 50 years, study shows

Average total testosterone levels in men have fallen by half over the past 50 years, according to new data presented at the European Society of Human Reproduction and Embryology’s annual meeting in London, sparking concerns about a potential male fertility crisis.

But Stefan Arver, associate professor of endocrinology at Karolinska Institutet and a testosterone expert, said the decline has not yet led to reduced fertility in men.

“It has not resulted in men being less fertile than before,” Arver told Swedish broadcaster SVT.

One possible explanation for the drop is the rise in obesity, which is far more common today than 50 years ago. Excess weight can lower testosterone levels without necessarily reducing the hormone’s effects.

As awareness grows, testosterone testing has become more accessible, with several providers marketing tests online. SVT reporter Oscar Lundberg booked a test to check his own levels.

“It was very easy to book. You could even get a discount code,” Lundberg said.