My advice, don’t. When in doubt, don’t. The times that I’ve let myself get talked into doing something I saw “red flags” about, I’ve always regretted. When I’ve stuck with my guns, even though once or twice it has been the wrong decision, I could live with it.
Wash your hands, avoid people who are sick, eat well and get plenty of rest. That’s better than any vaccine, imo.
Good advice in general, yet as I understand it, most flu viruses are airborne.
I can only speak for myself and say, I got the standard flu vaccine, but will pass on the H1N1 shot for its general lack of testing and that I wouldn't trust the government - especially this administration - at all. Though of course you're the pregnant one.... Congratulations for that!
That you seem to have an investigative frame of mind is a very good thing.
All the best, and God Bless You and Yours....