I realize my husband has an account at Sammy boys forum and he has been actively posting on it looking for prostitutes. I am pregnant right now. And devastated. We are PRs, got married 5 years ago.

If it were me, I would screenshot everything first. Google the username to see if anything sleazy pops up before confronting him. But before you confront him, ask yourself what do you want the outcome to be? To continue with the marriage or for a divorce? Would you be ready for the consequences that comes after the confrontation? Otherwise, it'd be best for both of you to meet a marriage counsellor for a more objective view.