Review of radiation therapy in the pregnant cancer patient.

Cancer diagnosed during pregnancy occurs in approximately 1:1000 gestations, and up to 4000 women per year in the United States receive radiation therapy during pregnancy. This article will review the effects of ionizing radiation exposure on the embryo and fetus, review the most common malignancies that present during pregnancy, review important treatment delivery considerations in those cases when radiotherapy is necessary during the pregnancy, and in a related topic, review fertility issues in females who receive therapeutic radiation before or during their reproductive years.