Hi! I had the same dilema. I ended up finding out I was pregnant when my daughter with CF was just over age 1. I was actually really grateful that my husband and I hadn't sat down to discuss our options yet. I figured, if my second child had CF at least they would have each other to understand. If my second did have CF, I feared I would be full of guilt, but after a lot of contemplation and prayer, I realized that I wasn't the one deciding whether or not my child had CF. Maggie (my 1st) wouldn't be the amazing, sweet, smart, funny kid that she is if she didn't have the exact genes that she has. And I spoke with adults with CF who have siblings with CF and they all said they were so happy to have grown up with someone who understood what they were going through. Their sibling was a gift to them.
I didn't get any testing during the pregnancy because of the risk of miscarriage. And it was difficult to wonder, but at the same time I was pretty calm. Luckily, my second doesn't have CF. I'm a big believer in the "everything happens for a reason" philosophy. There are so many things that can go wrong with any pregnancy. I recently had three friends who were/are pregnant - one is still pregnant and due any second, one lost her baby at 18 weeks, and one received a terrible diagnosis and the doctors don't think the baby will survive long after birth if he even survives the pregnancy. My friend and her husband have put it in God's hands and will love their baby for as long as they have him. Maybe you're not religious, but don't let fear take control. Do what your gut and your heart tell you, and do it with confidence and faith.