I've read a lot of the posts and although I've tried to stay out of this topic, I really feel like I should share. Below is responses driven from what others have said on the topic and farther down is actually a response directly to sknoell and her post-they may be a little bit repetitive, sorry.
I don't think any child with CF would be upset at their parents for not having another child because you didn't want to risk that child having CF. In fact my mom asked me, would you want me to have another child, knowing there was a 25% chance they could have CF-my answer? NO. I wouldn't want her to risk it, because even though it is only 25%, that is a lot, and I wouldn't want my sibling to suffer through what I suffer now. If my mom could have known there was a chance I would have CF, I would want her to have chosen not to have me.
It's not just because of all the medical issues I have to deal with and the pain and trying to breathe, but it's because I can see the pain that my disease has on my parents, my sister (different father who wasn't a carrier), my boyfriend, and my friends. My mom didn't know that there was a chance I could have CF and yet she still feels guilty, she truly feels it is her fault that I suffer. I HATE that she feels that. I HATE that someone I love has told me that they think killing themselves would be a better option than living without me when I die. I HATE that my little sister has gone to school crying because I'm in the hospital and simply for a tune up. I don't even want to imagine all the pain/suffering/anger that the people who love me will feel when it comes to the end of my life-knowing that I am the cause.
If my mom chose to have another child knowing there was a chance they could have CF I would HATE that decision and I wouldn't like her for doing it. I'd still lover her and be part of her life, but I wouldn't be happy that she did it.
As far as the idea that NOT having a child because they might have CF would make the current child with CF feel bad about themselves, well can't you also say that the parents wanting another child-hoping that that child wont be sick-hurt the CF child just as much, and in fact more so? I think they could understand their parents not having another child because they wouldn't want them to suffer like they do, I doubt they could understand their parents having another child hoping that they weren't like them, that would make them feel really bad about themselves. But I honestly think these two thoughts would only occur in a younger child, and a younger child doesn't need to know their parents reasoning behind having, or not having another child.
To sknoell, I don't think a child would neccessarily be resentful to you for having had them, but if you were to ask their opinion on you having another child I would bet that they would tell you not to do it, not to risk it. As far as them being happy they are alive, I'm sure they would. Given the choice of life or death I'd take life. But if we could go back in time and my mom could see that there was a potential that her child could have CF, I would happily support her decision in not having a child and me not existing. So in choosing life and death, I'd take life, but in choosing existing and not ever existing, I'd choose not ever exisiting.