First off, congrats on your pregnancy! How far along are you?
Although Cayston in the inhaled form is relatively new it was developed from an IV that has been around for a long time, Aztreonam. My doctor told that Aztreonam, the IV version of Cayston, is well tolerated and considered safe as far as medication and pregnancy go. Because the IV drug is considered a relatively safe choice during pregnancy then an inhaled form where less antibiotic gets into the blood stream is considered even safer. I would rather go on a Category B drug that has been used safely in IV form than allow an infection to develop and need more intensive intervention. I know pregnancy and CF is such a scary (and very exciting) event because not only do we worry about our own health, but also how our health and health regime might affect our developing baby.