Hi Jennifer, Actually, I was diagnosed after the loss. I was about 8 weeks post-partum when the symptoms started. My doctor initially thought it was post partum thyroiditis, but test revealed otherwise. My endro says I should wait 6 months after treatment to give each ovary 3 months to clear the eggs that were maturing when I took I131. He said that women have gotten prgnant almost immediately after taking the treatment without problem, but it would be a much safer bet to wait. This is due to the bladder being the method of elimination of the radioactivity and so close to the ovaries. Note: my internist agrees and both are great.