This isn't really an answer to your question, but this reminds me of this theory I once had. I was writing in my journal one day when I began to ask myself if it was possible for alters to have individual disorders. It got me thinking and the theory explained a lot of my unanswered questions, but I wasn't sure if it was possible. But if it is possible to have one of your alters get pregnant, I am now beginning to think that my theory is now possible.