Pregnancy and radiation - what patients need to know

Frequently asked questions

» Can I undergo X ray investigations while I am pregnant?
» How long after radioiodine treatment should I wait before getting pregnant?
» Can I breastfeed following radio-iodine treatment?
» Can a pregnant patient receive radiotherapy?
» Can I undergo a CT scan while I am pregnant?
» Is it important to know if I am pregnant for undergoing a CT scan?
» Previously I was given a protective apron or other shielding to protect me from radiation, but not this time. Why? 

» Can I undergo X ray investigations while I am pregnant?

Yes, if medically necessary and with certain precautions. The aim is to minimize both your and your child’s radiation exposure while still obtaining the necessary information for the examination. An unborn child is considered more sensitive than adults or older children to potential adverse radiation effects. For many examinations, such as X rays of the head (including dental X rays), chest and extremities, where the pelvic region is not in the direct beam, the dose to the unborn child is negligible. Health care providers may consider delaying procedures that would put the pelvic region and the unborn child in the direct path of the beam. If the procedure is essential to the mother’s healthcare, staff do take additional precautions and will be able to assess if shielding is necessary or not. 

» How long after radioiodine treatment should I wait before getting pregnant?

Women are recommended to avoid pregnancy for at least 6 months following radioiodine treatment. 

» Can I breastfeed following radio-iodine treatment?

Breast feeding must stop before starting radio-iodine treatment as there is a risk of damaging the infant’s thyroid, causing permanent hypothyroidism and increasing the risk of thyroid cancer.

» Can a pregnant patient receive radiotherapy?

Cancers located away from the pelvis may be treated by radiotherapy only after discussion with the radiation oncologist. Cancers in the pelvis will require careful consideration. Doctors will discuss with their patients whether to proceed with radiotherapy, delay the treatment until after birth, terminate pregnancy, or use alternative treatment.

» Can I undergo a CT scan while I am pregnant?

Yes, if medically necessary and with certain precautions. The aim is to minimize the unborn child’s radiation exposure. An unborn child is considered more sensitive than adults or children to potential adverse radiation effects. For many examinations such as CT of the head (including dental CT scans), chest and extremities, where the pelvic region is not in the direct beam, the dose to the unborn child is negligible. Doctors may consider delaying procedures that would put the pelvic region and the unborn child in the direct path of the beam. If the procedure is essential to the mother’s health, staff do take additional precautions and will be able to assess if shielding is necessary or not. 

» Is it important to know if I am pregnant for undergoing a CT scan?

Yes. For any examination involving direct exposure of the lower abdomen, pregnancy should be ruled out, or the pregnancy status should be verified as part of the justification process. 

» Previously I was given a protective apron or other shielding to protect me from radiation, but not this time. Why? 

Patient shielding was previously used to minimize the potential risks from radiation.  However, the equipment and our understanding of radiation effects have improved (or advanced). This dramatically reduces the radiation dose you receive, making the benefits of using shields negligible. Also, shielding may interfere with the anatomy being viewed or the automatic dose control equipment, which could lead to repeat examination. Staff take many other measures to limit your radiation dose according to your size and specific examination.