I am a long time away from being able to say "the most useful pregnancy advice given to me was..." But I can share my favorite advice. It came from my father in law, who told me the best prep I could be doing right now was to focus on my marriage (being close and united), instead of reading a bunch of parenting books. He said our marriage would have a huge impact on our child. ...While I think this is probably wise in ways I don't even know yet, I mainly took that as a perfect excuse to spend time with my favorite person. And on the eve of week 38 of trying to implement this advice, I'm just here to say that I regret nothing.