Of course, none of that says they cannot refuse to serve a pregnant woman, either.
How much are you willing top pay an attorney so that you have an opportunity to have a drink? Is it really worth it?
Even if you are in the right, there is an economic reality in play here. The easiest - and cheapest - way to proceed would be simply go to the next bar or nightclub.
Check airline rules for flying when pregnant ... I guess someone needs to sue them, too.