I read that the more pregnancies you have, it increases your chance of twins, is this true? I have 3 children with the same guy, this is my first baby with my new boyfriend & he thinks it'd be cool to have twins. my great gma (on my dad's side) is a twin but we haven't had anymore twins since. my mom got pregnant with fraternal twins with my little sister but the other one vanished. just wondering the odds!