How long do you have to wait to get Pregnant after a Radioactive Iodine Uptake?

I was having some minor thyroid problems after my daughter was born in Sept...Dr. sent me for Radioactive Iodine Uptake to check the thyroid...everything was fine and I did not receive a "therapy dose" after the exam...we want to start trying again this fall, but I have heard that you have to wait a full year after the uptake to get pregnant...