Comments by "worn down" (@worndown8280) on "Could Cousin Marriages Fix Falling Fertility Rates?" video.

Genealogical studies are showing around 6%, with higher levels around working class and poor, lower in wealthier families. Though these studies have been only done, to my knowledge, in European nations.
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@yeetdeets Yes but with companies like 23andme, and others, people are finding more and more that there family isnt. Ive found 2 in my family tree, but they were back in the 1600s. My family is German, so the 30 years war was a thing. You can hire a librarian at the Vatican to go through their archives, if the local church no longer has the records due to fire or war or whatever. It is expensive though. But when you have lots of family members to help with the bill it gets much cheaper.
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Blood tests were for when people with incompatible Rh types so they would know if they had kids, there was a high chance the woman would die. due to complications. That test is probably the greatest reason for the implosion of female death rates in child birth.
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