I think there's not much that live births have to do with your odds of miscarriage, it is all connected to the viability of the fetus, and if the sperm or the egg isn't ideal, the body rejects it. That being said, my grandmother was pregnant 10+ times and had two live births (unfortunately one of her children passed in an unrelated car accident.) while my mother was pregnant 6 times and had 5 live births.
Some women can carry children and others just have a harder time, there's no rhyme or reason to the miscarriages unless you have a diagnosed fertility issue.