Answer to Question #7250 Submitted to "Ask the Experts"
The following question was answered by an expert in the appropriate field:
I recently had an iodine-123 scan. Two days later I discovered that I was 12 to 14 weeks pregnant. I had no other reason to think that I was pregnant except for some nausea. What are the effects on me and the fetus at this stage of a pregnancy?
You had a diagnostic scan with a low exposure to iodine-123. This would not affect your fetus' thyroid and would not be responsible for increased risk of birth defects or miscarriage. Furthermore at 12 to 14 weeks the fetus has formed all the major organs.
If you are healthy, young, and have no reproductive problems or family history of reproductive or developmental problems, your risk for birth defects is 3 percent and for miscarriage, 15 percent (although at your stage miscarriage is much less of a risk). These are background risks with which every woman begins her pregnancy. Neither you nor I can change these risks. Good luck with your pregnancy.
Robert Brent MD, PhD