Im doing some unrelated reading and came upon this. The article goes a different direction, but I'm wondering if anyone has any references for this. The internet is not easily giving up info on sperm deterioration and their declining ability to give healthy children.

".. .the sperm of an 18-year-old man undergoes about 100 doublings before it becomes "mature," while for a 50-year-old man this number is around 800. With each doubling, the number of errors in the DNA increases, leading to accumulation of mutations in the sperm."

https://medicalxpress.com/news/2018-12-dna-genetic-diseases-cancer.html