Looks like disasters make the birth of a boy less likely than that of a girl, including in Kumamoto:
“A study published in August this year by Misao Fukuda at M&K Health Institute in Kariya, Hyogo, looked at births in areas hit by events that caused extreme stress. They included Hyogo Prefecture, after the Kobe earthquake of 1995; Tohoku, after the Great East Japan Earthquake of 2011 and subsequent nuclear disaster at Fukushima Daichii power plant; and Kumamoto Prefecture, after the 2016 earthquakes. It turns out that nine months after such disasters, the proportion of male babies born in those prefectures dropped by 6 to 14 percent.
What’s going on here? Perhaps sperm carrying the Y chromosome are more vulnerable to stress, or the male embryos themselves are more vulnerable. No one knows the answer. We also don’t know why, by the way, that even under normal conditions there is an inequality in the number of babies born of each sex: on average 105 boys are born for every 100 girls.”
– Kirk
