When is the best time to tell family ?

I'm 23 living with my boyfriend in an apartment owned by a family member. my family is not particularly fond of my boyfriend and has threatened me for dating him. we have been together about a year and a half, living together since October. now I'm 7 weeks pregnant and panicking my family will force me to abort or we will be kicked out. how is the best way to go about telling family like this ? how long should I hide it? I have not been able to calm down since I found out and not really sure where to go from here.