Eh, CT scan thing can be a bit worrying la, especially if you're pregnant or breastfeeding, best to go talk to your doctor about the actual risks for your situation, because they'll know your medical history better than anyone here can advise. A few of us mums have had to do imaging during pregnancy and the doctors were quite reassuring, but it really depends on why you need it and what stage you're at. If you're concerned, don't hesitate to ask your GP or specialist the specifics, they won't mind explaining!