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.

5. Old Dads Yield New Mutations

More Men Ditch Jobs to Become Stay at Home Dads and Care for Kids - Bloomberg

The average age for new U.S. dads has passed 30, Science

Raquel Welch - Wikipedia

Baby growth charts: Percentiles, reading a growth chart, and more

This Is How Parenting Has Changed Since the 1950s — Best Life

Prenatal Testing and the Future of Down Syndrome - The Atlantic

Ars Technica

Preterm birth - Wikipedia

Fathers of American newborns are getting older, study finds