Major Study Reveals Sperm Counts of Western Males Drops Significantly Over 40-Year Period
While male longevity has increased by an impressive 25 years over the past century, startling new research has revealed that while men may be living longer, diminishing sperm rates may mean there could be fewer men – and women – living in the future.
This bleak prognosis of human reproduction is just one takeaway from a massive and highly-regarded international study conducted by The Hebrew University of Jerusalem, which brought together medical investigators from the U.S., Spain, Israel, Denmark, and Brazil.
Led by Dr. Hagai Levine, the research team analyzed data from 185 previous studies and nearly 43,000 men living across North America, Europe, Australia, and New Zealand.
Investigators identified a significant drop – in both sperm count and sperm concentration (which refers to the amount of ejaculate produced for the sample) – from 1973 to 2011, nearly a 40-year span.
Overall, the results revealed a 52 percent drop in sperm concentration, while the total sperm count declined by 59 percent.
In the last few decades, other researcher teams also concluded male fertility was dropping in Westernized countries around the globe. Yet, those results and claims were mostly discounted because of population and methodology variances.
“There has been a longstanding debate among scientists as to whether sperm counts have decreased or not,” wrote Chris Barratt, professor of Reproductive Medicine at the University of Dundee in Scotland.
“But what’s different about this study is the quality of the analysis,” Barratt said. “It was done in a systematic manner, accounting for several of the problems that had affected previous studies, such as the method used to count sperm and comparing studies performed sometimes decades apart. As such, most experts agree that the data presented is of a high quality and that the conclusions, although alarming, are reliable.”
Journalist Ariana Eunjung Cha wrote about the study findings for the Washington Post, “The most important data points in the new study involved sperm concentrations for what are known as ‘unselected’ men who haven’t yet proven they are fertile.”
“There are men in the studies,” continued Eunjung Cha, “who are on the younger side and are not yet fathers or do not have partners who are pregnant.
Researchers estimated that these men had an average sperm concentration of 99 million per milliliter in 1973, but that that had dropped to an average 47 million per milliliter in 2011.”
These numbers are especially disturbing when you factor in statistics from the World Health Organization (WHO). The WHO considers men with a sperm concentration of less than 40 million to have an impaired chance of conceiving, while males with less than 15 million per milliliter are probably unlikely to father a child.
The study also revealed that where men live, may impact their reproductive capabilities.
Specifically, men residing in the first world or developed countries were adversely affected, while those living in South America, Asia, and Africa did not experience any degeneration of sperm during the same time period.
Could certain regions or cultures be affected differently?
Researchers don’t yet have an answer. Without further study and solid data, how geography fits into the declining sperm quality and rates puzzle remains a mystery.
The study also did not identify reasons why men are being affected in the West.
Most scientists believe there isn’t one single reason for the drop in male fertility, and instead point to theories that focus on numerous disrupters that affect sperm viability. For example, prenatal exposure to certain chemicals, exposure to numerous toxins after birth, stress, obesity, and even climate change are viewed as probable culprits.
Whatever the causes, the world scientific community is taking the study seriously.
Professor Daniel Brison, scientific director at the UK’s University of Manchester’s Department of Reproductive Health, are calling the study results a “wake-up call.”
Brison noted wider implications, “…there may be something in our environment that’s affecting health. Not just male fertility but male health in general, maybe health in general.”
“And if you look back over the last 50 years of these studies a lot of things have changed in our environment – plastics, introducing new chemicals into the environment, modern agriculture hormones, pesticides, and there’s just this concern that that’s what we’re seeing,” Brison said.
Furthermore, Brison theorizes that the cause of declining human sperm could go back generations.
“Exposure could be important when the men are in utero, when the mother is pregnant, or even their grandmother when they were infected with germ cells at that stage.”
With this new information, here are a few suggestions for advising male patients who are concerned about their fertility:
- Encourage male patients to avoid certain toxic chemicals which may affect fertility, such as bisphenol A or BPA.
- Stop smoking or better yet, never smoke.
- Overall, adopt a healthy lifestyle, including eating healthy, limiting alcohol intake, exercising, and reducing stress levels.
- Age also impacts male fertility. As men grow older, sperm count and quality of sperm declines. Consequently, banking sperm might be the right choice for some men.