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?

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

Yes, if medically justified and with certain precautions. The aim is to minimize the unborn child’s radiation exposure. An unborn child is considered to be more sensitive than adults or children to potential adverse radiation effects. For many examinations such as X ray of the head (including dental X rays), chest and limbs, where the pelvic region is not in the direct beam, the dose to the unborn child can be very low. 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, the doctors take special actions to keep the dose to the unborn child as low as possible. For example, pregnant patients can have their pelvic regions shielded during the procedure.

» 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 justified and with certain precautions. 

The aim is to minimize the unborn child’s radiation exposure. An unborn child is considered to be 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 limbs, where the pelvic region is not in the direct beam, the dose to the unborn child can be very low.

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, the doctors take special actions to keep the dose to the unborn child as low as possible. For example, lower exposure factors can be chosen and pregnant patients can have their pelvic regions shielded during the procedure.

» 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.