It is recommended that you wear loose clothing that is comfortable during a CT examination. In most of the cases, there is a hospital gown or apron provided by the radiographer that can be worn. It can be returned back once the examination is over. Metal objects would interfere with the images obtained. Hence it is advisable to remove things such as hairpins, jewellery, eyeglasses that you may be wearing. This would also largely depend on the specific area of the body being examined. The radiologist would advise you not to drink or eat anything a few hours before the examination. It is very important for women to inform their doctor if they have missed their periods or if they are pregnant because X-rays have been known to cause birth defects following exposure.