@ Sunny
DMP is right, they want declaration from pregnant visa applicants( given in guidelines http://www.cic.gc.ca/english//pdf/pub/dmp-handbook2009.pdf ), if a pregnant visa applicant is prepared to undergo a chest x-ray then she needs to consults her doctor before undergoing the x-ray and then special precautions are taken during radiography (eg. using a protective lead shield and waiting until at least the second trimester). It is true that these special precaution will definitely reduce the level of side effect but to a certain extent. Unfortunately, it is not 100% effective protection for developing fetus.
Another option. a pregnant visa applicant can also defer her chest x-ray, until after the child's birth. If the applicant declines to undergo a chest x-ray on account of the pregnancy, then a chest x-ray should be obtained and submitted after delivery, even though this will delay the IMA process and therefore the decision on her visa application. A pregnant visa applicant should advise the CHC about it beforehand.
The decision is totally the applicant's. So it is up to u people to go for X ray now or defer it untill delivery.
Best wishes
