If disease and the threat of mass extinction isn’t enough to get you worried about climate change, how about a declining sex life? According to a new study, climate change is one of the driving factors behind falling global birth rates, because fertility becomes compromised when temperatures soar.

Although summer may often be credited as the season for steamy romances, research conducted by the National Bureau of Economic Researchers recently found that hot weather is actually a serious mood killer. Their study looked at birth and weather records to investigate how temperature affected birth rates, and found people aren’t conceiving as much when it’s hot out.

Results revealed that from 1931 to 2010 there were about 1,165 fewer births nine months after days when it was over 80 degrees — a 0.4 percent decrease in birth rates. More importantly, the study found birth rates didn’t bounce back after these hot days, suggesting the heat has a direct effect on couples’ fertility, the researchers said.

While the difference in birth rates isn’t large enough to have a major impact on the global population just yet, it does help to humanize the higher temperatures caused by global warming. If it were to become a problem, however, it would affect places like the U.S. and UK, where birthrates are currently below the replacement rate — meaning citizens aren’t having enough children to maintain the population. Starting next year, there could be as many as 107,000 fewer deliveries in the U.S. due to predicted weather patterns, according to Natural World Report.

"I wouldn't say it is the end of human civilization, but I would suggest it is going to add to the cost of climate change," said lead researcher Alan Barreca, associate professor of economics at Tulane University, according to CNN.

This is not the first time researchers have noted a correlation between temperatures and human sexual activity. A study conducted by Trojan condoms earlier this year found rainy weather was most closely associated with sexual activity, and as many as 35 percent of Americans had turned down sex simply because it was too hot.

Scientists believe that in addition to turning people off sex, hot weather may also interfere with the hormones necessary for conception. For example, research has shown testosterone, the hormone that controls a man’s sex drive, gets depleted in warm temperatures. Additionally, in a 2007 study on sex during different seasons, researchers showed that men were more likely to rate women as attractive when they saw photos of women’s bodies (not faces) in the winter months when compared to the summer months — although the reason why was not confirmed.

Source: Barreca A, Deschenes O, Guldi M. Maybe Next Month? Temperature Shocks, Climate Change, and Dynamic Adjustments in Birth Rates. The National Bureau of Economic Research. 2015.