14 Day Rule in Radiology

While the 28-day rule applies to radiological examinations, which can take place throughout the 28-day cycle until a patient undergoes a missed period and is suitable for a low dose of radiological examination (chest x-ray). Thus, the focus here is more on the missed period and the possibility of pregnancy [6]. At this stage, the patient is assumed to be pregnant, unless the contrary is proven by a urine test for pregnancy to confirm the state of pregnancy. Depending on the type of radiological procedure, the corresponding rule (“10 days and 28 days rule”) is applied. If the number of cells in the conceptus is small and their nature is not yet specialized, the effect of damage to these cells is most likely to be observed in the form of implantation failure or undetectable death of the conceptus; Malformations are unlikely or very rare. Since organogenesis begins 3 to 5 weeks after conception, it has been assumed that radiation exposure in early pregnancy cannot lead to malformations. On that basis, it was proposed to abolish the 10-day rule and replace it with a 28-day rule. This means that a radiological examination, if warranted, can be performed throughout the cycle until a period is missed. Thus, the focus is on a missed period and the possibility of pregnancy. PIP: Procedures to ensure the safe use of X-rays to protect the developing embryo or fetus are described.

The effects of radiation on the developing embryo or fetus can lead to developmental disorders and cancer in children or later. The 1st trimester of pregnancy is a particularly critical period, with the exception of the 1.10 days after the beginning of the menstrual cycle when there is no risk of conceptus. The guiding principle is the 10-day rule, which states that the abdominal region (lumbar spine, pelvis, tailbone and hips) should not be irradiated after the 1.10 days of the menstrual cycle. The exceptions are patients on pills, sterilized, with a hysterectomy, or when the referring doctor considers that the X-ray saves lives. This 10-day rule has been modified to allow radiographic examination of patients of childbearing potential, provided that the patient is not pregnant. The responsibility for determining pregnancy rests with the attending physician, radiologist, radiologist or technician. The date of the last menstruation must be entered in an application form. Any missed or late deadlines are worrisome; The recommendation is to publish a warning about the risk of pregnancy in the diagnostic service. In addition, the radiologist/technician should ask privately if the patient might be pregnant. If the fetal risk is less than the lack of necessary diagnosis, examinations may be carried out, but care must be taken to minimize the radiation time or the number of films or the high dose of radiation to the fetus. Irradiation of other removed areas of the fetus, such as the breast, skull or extremities, can be performed at any time during pregnancy, provided that appropriate shields (lead aprons) are used to protect the fetus from X-rays.

Ultrasound examinations are preferred to determine fetal maturation, placental localization and viability of the fetus. This method is safe because it does not use ionizing radiation. If pelvimetry is necessary during pregnancy, it is necessary to determine the cost-benefits and take X-rays in the last trimester of pregnancy. The reminder is that all measures must be taken to avoid exposing the embryo and fetus to ionizing radiation. Safety standards must be met in hospitals and private clinics; The creation of a national radiation protection and regulatory authority is essential. X-ray operators need appropriate qualifications and training. The use of contraceptive methods should not exclude pregnancy. While the use of contraceptives reduces the likelihood of pregnancy, the effectiveness of the method used is a matter of professional judgment.

Therefore, in case of doubt, these guidelines should be followed (14, 16). If appropriate radiation protection measures are applied, it is unlikely that a pregnant worker in a radiology department will approach fetal dose limits. While radiation doses to the worker in a fluoroscopy suite are higher, the lead-containing apron keeps exposure at the waist level very low, if it is even measurable. » What is the ten-day rule and what is its status? In modern medical practice, there is a growing dependence on imaging techniques in most medical specialties. Radiation exposure during pregnancy can have serious teratogenic effects on the fetus. Therefore, checking the state of pregnancy before imaging women of childbearing age can protect against these effects. The lack of international regulations and standard protocols exposes patients to unexpected effects of fetal radiation and healthcare professionals to medical complaints. Recently, the American Academy of Radiology and the European Community for the Medical Protection of Ionizing Radiation published national guidelines for screening for pregnancy before imaging potentially pregnant women.

However, there are different methods of screening for pregnancy in different radiological centers. This review aims to discuss the latest guidelines for imaging women of childbearing age and highlight the need for international regulation to guide pregnancy screening prior to exposure to diagnostic radiation. For radiology institutions, it is important to have procedures to determine the pregnancy status of patients of childbearing potential before any radiological procedure that could lead to a significant dose to the embryo or fetus. The approach is not uniform across all countries and institutions. One approach is the “ten-day rule,” which states that “as far as possible, radiological examination of the lower abdomen and pelvis should be limited to the interval of 10 days after the onset of menstruation.” It should be noted that the dose limit applies to the fetal dose. This is not the dose measured on a personal dosimeter. A personal dosimeter worn to the waist by diagnostic radiologists is likely to overestimate the dose of the fetus. If the dosimeter is worn outside a lead apron, the measured dose is a significant overestimation and, although it can be used as an ascending dose of the fetus, if no other information is available, it is not recommended to use it to estimate the fetal dose. Fetal doses are unlikely to exceed 25% of the personal dosimeter measurement.