I respectfully disagree with the majority of posters here.
Talk to your Boss. The comment was TOTALLY inappropriate. Let him know that, and that you dont want to be singled out publicly . IF he had concerns about your specific safety, he should have discussed them with you *in private.*
That being said, the fact that he said something in public means that he was comfortable enough to say it adn not think that you would take offense, meaning that perhaps you arent seen as so different, after all. Or, he could just be really clueless as to what constitutes discrimination, like a lot of bosses out there. OTOH, he ignored the liver issue, which makes me think he was subconsciously more concerned about you than your male counterparts (which, sometimes, I cant blame them for, but that's another issue).
You dont want to make a big stink to him (DONT talk about it to anyone else at work either), but you do want to adress the fact that you were singled out for safety concerns in a manner that should have been addressed in private, and it put you in a bad position.
If the behavior continues, talk to HR.