It's a tough one to know for sure, I think alcohol effects everyone (and their fertility for that matter) differently.

Both times, DH and I have continued to drink and eat as we normally would and I'll be honest, we both love a drink It hasn't effected our TTC journey at all. I was off the pill 3 months when I fell PG with DD and we were on our first month of TTC when I fell PG this time - and we only DTD once that cycle

My DH isn't unhealthy but has a few beers most nights and some nights it's several beers or a few wines. We'd both normally have a drink 4-5 nights a week and as I said, it didn't effect our fertility whatsoever.