So much for hot sex. A recent study purports there are fewer births nine months after a heat wave. It found that an increase of about 21.600 Fahrenheit in summer temperatures reduces births the following spring by up to 6 percent. Researchers at the Kinsey Institute for Sex Research concluded that high temperatures could reduce people’s sense of well-being, which could result in a reduction in sexual interest. Another study found lower sperm counts and higher rates of miscarriage during hot weather.