The alarming decline in male+ fertility: unravelling the causes behind the crisis

  • PUBLISHED November 02, 2023
  • AUTHOR Donna

Key takeaways

  • Stress, smoking or exposure to certain chemicals, such as those in plastics, may disrupt the male+ reproductive system.
  • Lifestyle also plays a role. Obesity, lack of exercise and consuming fast food can all potentially reduce sperm’s effectiveness.
  • Male+ fertility has been declining at an alarming rate in recent decades. But infertility isn’t just a medical issue; it has deep emotional and societal implications too.

The alarming decline in male+ fertility: unravelling the causes behind the crisis

A volume of research conducted across decades is unequivocal – men+ today produce fewer and less healthy sperm than those who lived half a century ago. A systematic paper from 2017, analysing over 185 studies spanning four decades, for example, found a 60 percent decrease in sperm counts since the 1970s.

Individual research underscores the same conclusion – sperm quality across the world is declining, contributing to the struggles of people who are trying to conceive. 2 In fact, in about 35 percent of couples with infertility, a male+ factor is identified along with a female+ factor, while in an additional 10 percent infertility is attributed to male+ factors only.

What chemicals are bad for the sperm

Many reasons for declining male+ fertility can be traced back to modern-day lifestyle choices and environmental exposures. For example, it’s well established that certain pollutants and other toxins can decrease sperm concentration, motility (movement) and viability, defined as the percentage of live sperm in a semen sample. Pesticides, herbicides, heavy metals and toxic gases all act as endocrine disruptors that can potentially mess up the delicate hormonal balance in your body. 

One of the most prevalent endocrine disruptors is bisphenol A, also known as BPA. Typically found in plastic containers, water bottles and food packaging, BPA can leach into food and beverages, from where it sooner or later ends up in our bodies. Studies on rodents showed that BPA exposure can lead to a significant decrease in sperm motility, count and increased DNA damage inside the sperm head, breaking up the strands and making conception unlikely.

Heavy metals such as cadmium, lead and arsenic, present in food, water and cosmetics, are also known to harm sperm health. 6 Pesticides have the same damaging effect when they interfere with testosterone production and sometimes lead to fertility issues.

Air pollution, too, is associated with a similar impact on semen. People working on highways, for example, exposed to nitrogen oxide and lead released from car exhausts, were found to have reduced sperm motility and sperm movement compared to other men+ living in the same area.

Diet: avoid fast food, but stock up on fruits and veggies

An unhealthy diet is another source that contributes to a decline in male+ fertility. Overweight or obese men+ have lower sperm counts and motility than men+ who are of a healthy weight, studies have found. 8 Certain unhealthy foods can even change the molecular and physical structure of sperm.

A harmful diet is high in processed foods, saturated fats, simple carbohydrates and sugar, and lacks fibre and essential fatty acids. 9 On the other hand, fruits, vegetables, whole grains and lean proteins are your friends and may improve the quality of sperm. Some suggest following a Mediterranean diet that seems to protect male+ fertility. Certain individual foods such as walnuts may also be beneficial. In a small study of 117 participants, researchers assigned men+ to eat or not eat around 18 walnuts daily for 12 weeks. They found significant improvements in sperm vitality only in the nut group. 10

Stress and fertility don’t match

Stress can mess up our bodily functions in many ways and fertility is no exception.

The stress hormone called cortisol can interfere with other hormonal signals that manage sperm production. Researchers found that high levels of acute stress can lead to hormonal imbalances, reducing not only sperm production, but also its quality. 11 For example, a study from 2014 suggests that men+ who had faced two or more stressful life events in the past year had lower sperm quality compared to those who faced fewer stressful events. 12

There are many techniques men+ can take up to try to manage stress. Physical activity like running or yoga can relieve tension in the body and clear up your mind. Strenuous exercise, however, is not necessarily recommended as intensive workouts may decrease testosterone levels. Mindfulness and meditation are also widely used practices to keep stress at bay, and for some a simple chat with a friend can already make a big difference.

Smoking and alcohol abuse are sperm killers

When talking about harmful habits, smoking and excessive alcohol drinking will always top the list for their adverse effects on health, including fertility. Both activities have been found to reduce sperm count, motility and can even alter the shape and size of the sperm. Quitting smoking, as well as limiting alcohol consumption, is absolutely critical for men+ who are trying to conceive with their partner, as research suggests. 13 14

Like smoking, certain prescription medications such as antidepressants and recreational drugs have also been linked to a decline in male+ fertility. Marijuana use, for instance, has been shown to lower testosterone levels and decrease sperm count and movement. 15

Rethink your sauna visits

Dipping in a hot bath or spending time in a sauna surely feels good, but there’s a potential downside to these pleasures, especially if you indulge yourself too regularly. High temperatures can cause damage to its health since sperm feels best when the scrotum temperature is slightly cooler (around three degrees Celsius) compared to the body temperature. 16

In a recent experiment, a small group of men+ were told to use a Finnish sauna for 15 minutes, twice a week, for three months. At the end of the experiment, participants were tested and were found to have a lower sperm count and motility. Exposure to high temperatures in a sauna or other similar sources of heat, however, is typically not long-lasting and full fertility should return after some time of abstinence. 17

Male+ infertility shouldn’t be a taboo

Infertility, however, isn’t just a medical issue; it has deep emotional and societal implications too. This is an especially important consideration given the fact that male+ fertility issues are often ignored in public discussions.

For many men+, the inability to conceive can impact their self-esteem and trigger feelings of inadequacy or failure, as society often links masculinity with the ability to father children. This emotional toll can lead to increased stress, anxiety, or even depression, affecting an individual’s overall quality of life.

In relationships as well, infertility can add significant stress. The pressure to conceive can create tension and potentially strain the relationship, often leading to a sense of isolation or frustration. This impacts the affected individuals and their partners, emphasizing the importance of emotional support and open communication.

We believe it’s important to keep the conversation going, promote reproductive health and support those facing infertility challenges. To learn more about male+ infertility, including what possibilities men+ have to overcome the challenges, jump over to our recent article.


Article overview
This site is registered on as a development site.