Answer to Question #2989 Submitted to "Ask the Experts"

I am a nuclear power plant worker (age 38) and I am exposed to radiation on an intermittent basis. My wife and I are considering pregnancy and are worried about the effects of radiation on sperm. In the last couple of weeks I have received a dose of around 20 mrem. Is this something that should cause us to postpone fertilization attempts?

Thank you for your inquiry about the reproductive risks of radiation to your sperm before your wife becomes pregnant. Preconception radiation risks have been studied in two large populations, women and men who have been treated for cancer and have mothered or fathered a child, and the Atomic Bomb survivors. Both of these populations have been extensively studied and in neither population is there an increase in reproductive risks, although theoretically one would expect an increased risk of genetic abnormalities.

Based on the theoretical risks we advise women who have had their ovaries exposed to radiation to wait for three menstrual cycles before attempting to become pregnant. Men who have been exposed should wait at least two spermatogenesis cycles, which is about four months. In your case the exposure is so low, that it really does not matter. A dose of 20 mrem is very low from the standpoint of genetic risks.

I wish you and your wife well in your future pregnancies. Remember that every man and women with a normal personal and genetic family reproductive history has the background reproductive risks which is 3% for birth defects and 15% for miscarriage. We cannot change those risks, as yet.

Robert Brent, MD, PhD