Prenatal radiation exposure in diagnostic and interventional radiology

The exposure of a pregnant woman to X-rays is an event that can cause uncertainty for all concerned. This review provides guidance on how to assess such a situation and how to determine the dose to the unborn child. In general, the use of X-rays in pregnant women in radiology should be avoided. If possible, alternatives should be used, or examinations postponed to a time after the pregnancy. This review gives a summary of the procedure for determining the radiation exposure of a pregnant woman.

Based on the previous report of 2002 and the literature on prenatal radiation exposure published thereafter, the DGMP/DRG report on the procedure for the assessment of prenatal radiation exposure was adapted to the current state of science and technology.

Typically, only relatively low radiation exposures of less than 20 mSv occur for the unborn child in X-ray diagnostics in the vast majority of cases. At these dose level the additional risk of damage to the embryo or fetus caused by the radiation is low and therefore only a rough conservative estimate using tabulated values are made. Only in a few types of examination (CT and interventional radiology) higher doses values might occur in the uterus. Instead of dose estimates (step 1 in the two-step model) in these cases the calculation of dose (step 2) are required and further action by the physician may be necessary.

During the assessment, it is useful to initially use simple conservative estimation procedures to quickly determine whether a case falls into this large group less than 20 mSv, where there is a very low risk to the unborn child. If this is the case, the pregnant woman should be informed immediately by the doctor who performed the examination/treatment. This avoids a psychological burden on the patient. The DGMP/DRG report suggests a relatively simple, clearly structured procedure with advantages for all parties involved (physician, medical physics experts, MTRA and patient).

· The DGMP/DRG report on prenatal radiation exposure describes the procedure for calculating radiation exposures and the associated risks for the unborn child.. · Using the two-step model, only a simple assessment based on the first step is necessary for most prenatal radiation exposures.. · With the given tables it is possible to estimate individual risks for the unborn child taking into account the radiation exposure.. · Only in the rare case that the first estimate results in a uterine dose larger 20 mSv a more accurate calculation is necessary..

· Fiebich M, Block A, Borowski M et al. Prenatal radiation exposure in diagnostic and interventional radiology. Fortschr Röntgenstr 2021; 193: 778 - 786.