I am guessing that they are considering the DDF508 to be the most "severe form of CF". I belive that most prenatal screenings only check for the first 45 or so genes?? Most likely it is these pregnancies that are being aborted.
Re: your second post. First let me say that I do not have health insurance, so I have not been tested for CF, but I absolutely am a symptomatic carrier at the very least. I have always had chronic sinus issues, and I was dx with asthma many years ago. Both of these issues have gotten progressivly worse for me over the years. Not to mention the IBS symptoms.
I think that a lot of carriers may one day be dx as we find new genes. I also think that more people are being dx, in part, because of sites like this. Just look at the number of parents who come here looking for answers, and who then push their docs to do testing that they were being denied. If not for the education available on the internet today, a lot of these children wouldn't be dx until much later in life when their symptoms simply can't be ignored or explained as other ailments any longer. My son was 15 before he was dx. I did not have access to the information we have today. If I had, I'd have pushed until I got the answers.
I'm not sure if much of that made sense. I'm working, and have had to answer the phone a couple of times while posting. Anyway, I think that we are seeing "carriers" who may have another undiscovered gene out there who's symptoms progress, as CF does, and that gives them the "increased risk" you are reading about. Just my 2 cents.
Stacey