Why is Male Fertility Decreasing?

Why is Male Fertility Decreasing?

Currently, more than 80 countries, including the U.S., have birth rates below the population replacement level of 2.1 births. By 2050, it is expected that 75% of all nations will have a birth rate that is lower than population replacement. At the same time, the number of births per person has declined from 5 in 1964 to 2.4 in 2018.

Reasons for the decline in births is a multifaceted issue and contributing factors include people choosing to have smaller families, changing cultural norms, having kids later in life, and the rising costs of raising children. But there may also be a more alarming reason: endocrine-disrupting chemicals in our environment. An endocrine-disrupting chemical is an agent that has the potential to cause dysfunction in hormone production. This in turn can cause disturbances in sperm production leading to male factor infertility. 

That is the subject of a new book by Mt. Sinai Medical School epidemiologist Shanna Swan called Count Down: How Our Modern World Is Threatening Sperm Counts, Altering Male and Female Reproductive Development, and Imperiling the Future of the Human Race. Swan also co-authored a study published in 2017 that concluded that total sperm count among males in Western countries had decreased 59% between 1973 and 2011. According to Swan, if the current global sperm count trend continues, it will reach zero by 2045. That means the median male would effectively have zero viable sperm since sperm count is related to overall semen quality.

In her book, Swan examines how endocrine-disrupting chemicals found in common products such as cleansers, shaving cream, water bottles, cosmetics, and many forms of plastic products are affecting human fertility and sexual development. These effects include higher rates of miscarriages, genital birth defects among boys, and earlier puberty among girls. Swan considers decreasing fertility to be a crisis on par with climate change, writing that it has the potential to threaten human survival.

To reduce the chemical footprint in your home, Swan suggests doing the following: 

  • Buy organic produce, whenever possible.
  • Avoid heating plastics in the microwave.
  • Banish air fresheners.
  • Say no to plastic bags.
  • Filter your drinking water.
  • Consider switching food storage containers from plastic to glass, metal, or ceramic.
  • Replace nonstick cookware with cast-iron or stainless steel.

Alternatively, a recent article in the New York Times presented some alternative research that shows the decline in male fertility may not be related to EDC or as urgent as Swan describes. It concludes that the impact of EDCs on reproductive health is not well studied.

Sperm Donors are Needed More Than Ever

While Swan’s research and conclusions will continue to be studied and debated, there is no doubt that it is important to take care of your health and donor sperm is currently in high demand. If you are a healthy male between the ages of 18 and 39, Seattle Sperm Bank encourages you to apply to become a sperm donor. Learn more about the process on our website or contact one of our donor coordinators with questions at (858) 732-8500 or cs@seattlespermbank.com.