Hi Lauren. I'm 37, a stay at home mom and have a 10 month old baby. My CF is mild still. Even with my good health and only doing one treatment a day, I have to say motherhood is quite the challenge. Still, I exercise every single day even if it is only a 30 minute stroller walk.
If your health is still good with PFT's above 70% then a pregnancy shouldn't be too hard, it's taking care of the baby that is the hard part. A lot depends on how your partner feels too since that person could become a single parent. My husband accepts that and wants me to have one more child. He doesn't know about a third child but that could be the case for anybody! In my case I could live for many more years so for us it's hard to justify not having the family we planned on. But the realities of CF hold true for me just as much as any other CFer. We just don't know.
When deciding to have kids you also need to consider how much help you will get aside from what your spouse does. Will your family or friends help out? Do you have enough money to hire help if you don't have much of a support system? Will you be able to stay at home? Will you be able to work all day and care for a baby at night? Etc... There's a lot to think about and everyone's situation is different.
For me, I have almost no outside help so I do all of the cleaning, laundry, etc. plus care for my baby 12 hours a day alone while DH is at work. Not easy but I let go of the idea of things being perfectly clean and neat! I just do what I can and don't worry about the rest. I hope this helps. <img src="i/expressions/face-icon-small-smile.gif" border="0"> Bonnie