I saved enough milk for about 2 months when we found out that I would have to have my thyroid “killed” with radioactive iodine. After taking this medication, breastfeeding would have to end so the radioactivity wouldn’t pass on to her through my milk. At 8 months she was weaned onto formula and we had a horrible time with it. For 4 excruciating weeks I couldn’t hold her at all because I was too radioactive for her to be near me. It was a very difficult time for all of us.