How to avoid drinking at office Christmas party!!

I am 11 weeks pregnant and haven’t told my coworkers yet. I don’t plan on telling them until a little further along, however we have the office Christmas party tomorrow night. Already, one of my coworkers said before leaving today “I can’t wait to be sitting down having drinks with everyone tomorrow!” … how can I avoid drinking without having to tell EVERYONE at the Christmas party??? Help pls 😩