CAMRT Radiography Practice Exam

What is the most likely radiation-induced effect on a fetus during the first trimester?

1. Physical deformities

2. CNS damage

3. Growth retardation

4. Malformations of limbs

The correct answer is: CNS damage

During the first trimester of pregnancy, the developing fetus is particularly vulnerable to the effects of radiation exposure. One of the most critical developments during this period is the formation of the central nervous system (CNS). Exposure to ionizing radiation in the first trimester can lead to significant and severe damage to rapidly dividing neural cells, leading to a variety of developmental abnormalities in the brain and spine. CNS damage can manifest in various forms, including intellectual disabilities, microcephaly, and other neurologic impairments. This susceptibility stems from the unique and sensitive developmental processes occurring during this early stage of gestation. As the fetus grows and matures through the later stages of pregnancy, the risks associated with radiation exposure shift, often resulting in different types of malformations or growth issues. While physical deformities, growth retardation, and malformations of limbs may also occur due to radiation exposure, the CNS is particularly susceptible to damage during this critical first trimester window, making CNS damage the most likely effect of radiation exposure at this time.