Well.. I'm not a 100% follower of all of the pregnancy don'ts. But Kombucha is fermented so there's alcohol in it. I'd say once or twice a week would be better than daily, but that's just my unprofessional thought. You might need to look up the brand you are drinking and find out exactly how much alcohol is in it and then ask your MD about it. Otherwise, they probably will have no idea what you're talking about.
BTW I love Kombucha! I haven't had any since expecting for the reasons above, but also because I'm one of the lucky ones that still throws up every day.