In 2017, Dr. Shanna Swan and her research team made an alarming discovery: Western men have experienced a 50% decline in sperm counts over the past 40 years. How did this happen and what does this mean for our future?

Dr. Swan came to her conclusions after examining 185 studies involving close to 45,000 healthy men. The result sent shockwaves around the globe—but the story didn’t end there. It turns out that our sexual development is changing in broader ways, for both men and women and even other species, and that the modern world is on pace to become an infertile one—by 2050 a large section of the  global population will need technological assistance to procreate.

In the alarming new book COUNT DOWN, Dr. Swan and Stacey Colino unpack research that reveals how both lifestyle and chemical exposures in our environment are affecting our fertility, sexual development and general health as a species.