Hyperemesis is truly horrible - I know - I had it for 4 months solid. I guess I was unlucky to have it that badly BUT it never occurred to me to go to hospital - least of all in an ambulance! What for? Your pregnant - that's what happens sometimes. I guess there are a small percentage of people that could have other complications as a result but even so, if you can walk and talk or as in my case drive and still be sick then hey - just drive there yourself if you are that worried.