what do you think?

hello... I've been thinking of this for a while and I wanted to know what other women think. I've been married 11 years. We have 2 daughters. our relationship is not the best and I am not 100% sure if I will stay with him for the rest of my life. heck for the next year! the thing is that I want another baby. :) . he does too that's not the problem. the problem is..should I have another baby with a man I don't even know I will stay with? this way all my kids have the same dad? or I shouldn't even bother? I want another child so I am leaning more towards trying to have another one with him. what do you think?