Something worrying is happening to men's penises across the world

We’re constantly told that “size matters”, particularly when it comes to a specific male organ.

For that reason, you might think that it’s good news for mankind that a new trend has been spotted in the evolution of this bodily appendage.

A study analysing penis sizes between the years 1942 and 2021 has found that the average length of the male member, when erect, has increased significantly over the last 30 years.

And whilst this might sound like a positive development overall, the reasons behind the growth pattern leave significant cause for concern.

The research examined penis length data from 55,761 males, taken from across the world over the past 80 years, IFL Science reports.

It excluded any studies which featured self-reported measurements, relying solely on those recorded by an investigator. And it also only included measurements taken "from the root (pubo-penile junction) of the penis to the tip of the glans (meatus) on the dorsal surface".

Interestingly, no changes were found in the length of flaccid or stretched penises, however, erect penises saw a significant boost in size.

"Erect length increased significantly over time in several regions of the world and across all age groups," the team wrote in the study.

"After adjusting for geographic region, subject age, and subject population; erect penile length increased 24 percent over the past 29 years".

That's a boost from 12.3 centimetres (4.8 inches) to 15.2 centimetres (6 inches) in just three decades.

Penises have grown, on average, by almost three centimetres in just under 30 years(iStock)

The authors stressed that there was nothing locker-room-related in their motivation to compare penis sizes over time.

Rather, they decided to launch their investigation after observing other changes in men's reproductive health in recent years, such as declining sperm count.

"Given the trends we'd seen in other measures of men's reproductive health, we thought there could be a decline in penile length due to the same environmental exposures," lead author Michael Eisenberg, of Stanford Medicine, said in a press release.

And whilst their findings showed quite the opposite, Eisenberg still believes that the size increase could be down to environmental issues.

"There could be a number of factors at play, such as chemical exposure, like pesticides or hygiene products, interacting with our hormonal systems,” he said.

“These endocrine-disrupting chemicals – there are many – exist in our environment and our diet."

He continued: "As we change our body's constitution that also affects our hormonal milieu.

“Chemical exposure has also been posited as a cause for boys and girls going into puberty earlier, which can affect genital development."

The team also acknowledged that additional variants, such as the techniques used to record length, temperature, and arousal state of the participant, could impact the results.

However, they believe that the apparent trend warrants further investigation, given the implications it could have for male reproductive health overall.

"The increase happened over a relatively short period of time," Eisenberg noted.

"If we're seeing this fast of a change, it means that something powerful is happening to our bodies. We should try to confirm these findings and if confirmed, we must determine the cause of these changes."

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