While no country has a perfectly even sex ratio, normally researchers would expect roughly 105 male births to every 100 female births.
Compiling data from over 200 nations – including 10,835 observations, and 16,602 years of information – the authors noticed a shocking number of countries have strayed from this mark.
“The estimated regional baseline values differ significantly from 1.05 for the majority of the regions we study,” the authors write.
“In addition, almost half (88 out of 212) of the estimated country-level baseline values, accounting for ethnic difference across countries within a region, are significantly different from 1.05.”
Of those 88 countries with higher-than-normal ratios, the authors pinpointed a dozen that looked worrisome.