Radiation exposure during pregnancy

The procedures for insuring safe use of X-rays to protect the developing embryo or fetus are described. Radiation effects on the developing embryo or fetus may produce developmental abnormalities and cancers during childhood or later. The 1st trimester of pregnancy is a particularly critical period, except for the 1st 10 days after the onset of the menstrual cycle when there is no risk to the conceptus. The guiding principle is the 10-day rule stating that the abdominal area (lumbar spine, pelvis, coccyx, and hips) should not be irradiated after the 1st 10 days of one's menstrual cycle. The exceptions are patients on the pill, sterilized , with a hysterectomy, or where the referring physician considers the X-ray life saving. This 10 day rule has been amended to permit radiographic exam of female patients of reproductive age, provided the patient is not pregnant. Responsibility for pregnancy determination lies with the referring physician, the radiographer or radiologist or technician. The date of the last menstrual period should be entered on a request form. Any missed or overdue period is of concern; the recommendation is to post a warning about pregnancy risk within the diagnostic department. Also, the radiographer/technician should ask privately whether the patient may be pregnant. Where fetal risk is less than not making the necessary diagnosis, exams may be made, but care should be taken to minimize irradiation time or number of films or high irradiation dose to the fetus. Radiation of other areas remote from the fetus such as the chest, skull, or extremities may be conducted at any time during the pregnancy, provided proper shields (lead aprons) are used to protect the fetus from X-ray beams. Ultrasound examinations are preferred for establishing fetal maturation, placental localization, and fetal viability. This procedure is safe because it does not utilize ionizing radiation. When pelvimetry is necessitated during pregnancy, the cost benefits must be determined and X-rays taken during the last trimester of pregnancy. The reminder is that all steps should be taken to avoid exposing the embryo and fetus to ionizing radiation. Standards of safety need to be maintained in hospitals and private clinics; establishing a national radiological protection and regulatory body is essential. X-ray operators need proper qualifications and training.