I am an endocrinologist in Maryland. I have a 35 y/o woman with hx Grave's just had RAI in mid Jan 2006, had negative pretreatment pregnancy test and now came in today and is pregnant. I had previously counseled the couple multiple times about avoiding this issue. Anyway, what would be your advice as to the potential risks to the fetus. The couple is thinking of terminating the fetus.
If the patient was treated as seems likely prior to the 12th week, the baby's thyroid should be spared. However the infant did receive several rads of radiation from the isotope present in both the mother's and the infant's body.The amount isin the order of5-10 rads depending on dosage of 131-I. This cariesa low risk of genetic damage or malignancy, that is difficult to quantitate.And it is worth remembering that every pregnancy carries a risk of about 4% for some birth abnormality due half to genetic effects and half to “other factors”. To my knowledge there is no blanket indication for pregnancy termination, but it is easy to understand the mother's apprehension. The decision may relate to questions including desire for this pregnancy and difficulty of conceiving.
L De Groot, MD