US dads of newborns are greying—percentage over 40 doubled since the 70s

Age increased across the board, in different races, education levels, and regions.

Baby boomers - Wikipedia

Newborn respiratory rate: Everything you need to know

Millennials Aren't Having Kids. Here's Why That's A Problem For Baby Boomer Real Estate & Retirement

Single, childless and nearing 40, I saw one real option

5. Old Dads Yield New Mutations

I Grew Out My Grey Hair At 42 - Chatelaine

2017 Ars Technica