Climate change has been blamed for many things over the years. Never, until now, has anyone thought it was possible to see it as a kind of contraceptive.
Hot weather leads to diminished “coital frequency,” according to a new working paper put out by the National Bureau of Economic Research. Three economists studied 80 years of U.S. fertility and temperature data and found that when it’s hotter than 80 degrees F, a large decline in births follows within 10 months. Would-be parents tend not to make up for lost time in subsequent, cooler months.
An extra “hot day” (the economists use quotation marks with the phrase) leads to a 0.4 percent drop in birth rates nine months later, or 1,165 fewer deliveries across the U.S. A rebound in subsequent months makes up just 32 percent of the gap.
Built-in population control?