Thanks for this!
STIs have been the biggest fear for my wife in our conversations. She spent a lot of time in college doing HIV testing at a needle exchange and at one point wanted to go into HIV/AIDS research, so she's read many, many scary things and seems to fear that the moment one of us has a sexual relationship with someone else (even with barriers) we will contract HIV and DIE.
(No, seriously, one of her thoughts was that only one of us should be sexually involved with others at a time, just in case, because she wouldn't want to leave our yet-to-be-conceived child an orphan.)
That said, I fully intend to use barriers until proof of disease-free status is in hand!