Should i tell my ex that i am pregnant with his child?

this seems like a no-brainer im sure but let me further explain. The reason we broke up was a pretty serious one. He has some habits that aren't so great but definitely aren't so great for children. Upon us (before i even knew i was pregnant obviously) having a hypothetical question about children he said he wouldn't stop these habits (smoking included) and i simply stated that i wouldn't have my child around that. From that he basically threatened my life pretty much saying he would kill me (even explained how) if i tried to "leave" with his child! this was even worse because i never said i would leave just that i wouldn't have my child around unhealthy things. Needless to say this was the moment that i broke up with him! Of course he tried to apologize later and claim it was in the heat of the moment (he's an intense person) however that's just not something i take lightly and could not forgive him. and here i am a month later preggers.............THOUGHTS?!?!?!