Q&A: Breastfeeding After A Radioactive Iodine Treatment?
You'll be able to breastfeed future children, but you will probably need to wean your current baby before starting this treatment. Radioactive iodine treatment (I-131) does enter your breast milk and could expose baby to radiation. It is recommended that nursing moms stop breastfeeding several days (or weeks) before the treatment begins and then pump and dump for several weeks after therapy to reduce the exposure of your breast tissue to radiation. (You'll also need to hold off on getting pregnant again for about a year, since your ovaries will be exposed to radiation.)