Study: ‘Climate Change Could Alter the Human Male-Female Ratio’
Since the 1970s, temperature fluctuations from the norm have become more common in Japan, and at the same time there has been an increase in the deaths of male fetuses, relative to the number of deaths of female fetuses in that country, according to the study.
Over this period, the ratio of male to female babies born in the country has been decreasing, meaning there have been fewer and fewer male babies born relative to the number of female babies born.
http://www.livescience.com/48070-male-fetus-climate-change.html