[User23]

No, it’s really not. The rate of increased birth defects for older fathers is quite small[1]. It’s advanced maternal age where you see the multiple orders of magnitude greater chance of serious problems.

[1] https://pubmed.ncbi.nlm.nih.gov/17164268/

[janeway]

It’s fair that my comment is not supported. The evidence is sporadic in both directions in fact. The paper linked is a big study but very weak association results. Here is a good review that includes the most plausible interpretation of the genetics.

https://pubmed.ncbi.nlm.nih.gov/36833413/