As Elis says, call social services.
If at all possible, you can help your parents (all three), get informed on the subject of what you are going through. Maybe even becoming a bit harsh on the severity that it is causing you, to even consider the fact you would rather not live if the route so governed would not be in your favor.
Some parents are thick headed, especially when it comes down to "what's good" for their children. Until they realize their way is not the right way of how it works. Maybe putting a big perspective on what it is, how emotional it is for you, to the even severity it could cause you physically. If they love you enough, they will eventually come to terms, but depending how you go about telling them how it is you really feel. And I am saying telling, not inquiring or asking them, but flat out putting it out there. This is though a kind of last resort method to stick to. The best bet would be rather a group therapy session, so they can understand your point of view from a "professional," I put that word in parenthesis because in actuality we are the professionals of our own reality, and everyone else is only a mediator in the grand scheme of it all.
Of course even if it were attempted forced hormone of the wrong cycle, you could always stand up and say you will not take it otherwise, as you are your own individual, and your mom should understand that, and respect it.
Kate <3
Always remember to smile your face