This article cites research on the decline in the proportion of boys born after the 2016 earthquakes. It says that, even when such measurable changes in birth ratios occur, they don't last long.
I posted about this research once before:
https://www.facebook.com/Kumamotoi/posts/2336449343095151
-- Kirk
Climate change will affect how many boys are born worldwide, scientists say
Worldwide, the sex ratio at birth averages between 103 to 106 males born for every 100 females; however, climate change and its effects on the environment in which pregnant women live will alter this ratio, research suggests.