Breastfeeding, Pregnancy & Radioactive Iodine (RAI)
Radioactive iodine (RAI) is an important part of treatment and follow-up in certain thyroid cancers. Because it affects the thyroid tissue in both mother and baby, specific precautions are essential during pregnancy and breastfeeding.
Pregnancy and RAI
- RAI must not be given during pregnancy. Radioactive iodine can cross the placenta and permanently damage the baby’s thyroid gland.
- If you are planning RAI, you must avoid pregnancy for at least 6–12 months after treatment, depending on your treating doctor’s advice.
- A pregnancy test is mandatory before every RAI therapy.
Breastfeeding and RAI
- You must stop breastfeeding completely before RAI. Breast tissue absorbs and secretes iodine, which can increase radiation to the breasts and expose the baby.
- Breastfeeding should be stopped at least 6–8 weeks before RAI to allow milk production and iodine uptake in the breast tissue to reduce.
- Once breastfeeding is stopped for RAI, it should not be restarted for the same child.
- After RAI treatment, you may breastfeed future children normally after the recommended waiting period (usually 6–12 months before conceiving again).
Conception After RAI
- Women: avoid pregnancy for 6–12 months after RAI.
- Men: avoid fathering a child for 3–6 months after RAI.
Key Points to Remember
- Do not take RAI if pregnant or breastfeeding.
- Stop breastfeeding 6–8 weeks before RAI.
- Pregnancy should be planned only after the safe waiting period.
These precautions ensure safe and effective thyroid cancer treatment while protecting the baby.