sperm count decline

Frequently asked questions on the new sperm count decline study

Sperm counts are declining everywhere — the implications are huge.

What is happening with sperm counts?


This study shows, for the first time, that sperm counts are declining everywhere, not only in North America, Europe, Australia and New Zealand, which was shown previously, but also in South America, Asia and Africa. This new analysis found that sperm count globally dropped by more than 50% between 1973 and 2018, and that the decline is accelerating: Since 1972, sperm count has dropped by about 1% each year. Since 2000, the annual decrease has been, on average, more than 2.6%.

What do lower sperm counts this mean for our health?

This accelerated decrease in global sperm counts means more people will need to use assisted reproduction to get pregnant. These findings imply more than decreased fertility; lower sperm counts are linked to more disease later in life (cardiovascular disease, diabetes and reproductive cancers) and a shorter life expectancy.

Why are sperm counts declining?

The decline is too rapid to be due to genetic causes alone. Some risk factors for lower sperm counts have to do with lifestyle; smoking, obesity, stress and binge drinking. In addition, environmental chemicals — particularly those that can alter the body’s hormones called endocrine disrupting chemicals (pesticides, phthalates, BPA, PFAS chemicals and others) — have been shown to reduce sperm counts and quality and are likely contributing to this decline.

What can be done about lower sperm counts?

While scientists continue to tease out the causes, men should avoid smoking, a sedentary lifestyle, excessive weight gain, drug and alcohol abuse, and potentially toxic chemicals. This means buying organic food when possible or washing fruits and vegetables that may have pesticide residues. Another good idea is avoiding plastics in food contact materials and personal care and household products that contain phthalates and other endocrine-disrupting compounds.

Read more about the new study: A new analysis shows a “crisis” of male reproductive health

Watch Dr. Shanna Swan discuss the work and implications

A view of solar panels against a cloudy day

‘We’re hardly producing any power’: Can Europe’s solar boom survive a cloudy winter?

A prolonged period of cloudy and windless weather can throttle Europe's solar and wind generations, often causing the grid to rely on polluting back-up sources.
A view of a row of solar panels extending over the water

Solar above, fish below: Double-decker farm's vast energy potential

Floating solar panels over the world’s fish and shrimp ponds could generate 4,100 terawatt-hours of electricity, avoiding up to 2.5 billion tons of emissions.
A view of wind turbines silhouetted against a darkening sky

Democrats plan to push clean energy in Congress as Trump backs fossil fuels

Some Democrats are promising to push for more clean energy to help tackle rising energy costs when they take control of Congress in January.
A small Nepalese girl carrying her younger sibling on her back

Climate change is bringing dengue fever to the high Himalayas

As Nepal’s mountains warm, mosquitoes are spreading dengue, once strictly a lowland disease, to higher-elevation, densely-populated areas.
A closeup of a human hand with a large mosquito on it

Drought driven by climate change is redefining how disease spreads, study finds

As climate change intensifies, drought is widening globally, causing alterations in water-dependent pathogen patterns, leaving scientists scrambling to understand how infectious disease transmission is evolving.

Aerial view of several rows of solar panels in a green field

COP31 host Türkiye is home to one of Europe's largest solar farms. Why can’t it kick coal?

As Türkiye prepares to host the UN climate summit, one critic describes the country's climate targets and policies as “critically insufficient”.
A yellow skid-steer loader in front of destroyed homes on January 13, 2013 in Lavallette, New Jersey in the aftermath of Hurricane Sandy
Credit: Glynnis Jones/BigStock Photo ID: 41233060

Disaster-prone communities face cuts and slowdowns in federal help

The Trump administration is scaling back or stalling investments that help vulnerable places harden themselves to rising flood and fire threats.
From our Newsroom
Multiple Houston-area oil and gas facilities that have violated pollution laws are seeking permit renewals

Multiple Houston-area oil and gas facilities that have violated pollution laws are seeking permit renewals

One facility has emitted cancer-causing chemicals into waterways at levels up to 520% higher than legal limits.

Regulators are underestimating health impacts from air pollution: Study

Regulators are underestimating health impacts from air pollution: Study

"The reality is, we are not exposed to one chemical at a time.”

Pennsylvania governor Josh Shapiro speaks with the state flag and American flag behind him.

Two years into his term, has Gov. Shapiro kept his promises to regulate Pennsylvania’s fracking industry?

A new report assesses the administration’s progress and makes new recommendations

silhouette of people holding hands by a lake at sunset

An open letter from EPA staff to the American public

“We cannot stand by and allow this to happen. We need to hold this administration accountable.”

wildfire retardants being sprayed by plane

New evidence links heavy metal pollution with wildfire retardants

“The chemical black box” that blankets wildfire-impacted areas is increasingly under scrutiny.

Stay informed: sign up for The Daily Climate newsletter
Top news on climate impacts, solutions, politics, drivers. Delivered to your inbox week days.