Journal of Radiology
Open Access

Radiation; Pregnancy; Biological effects

Introduction

Radiation is defined as the transmission or emission of energy in the form of waves or particles through a material medium or space [1]. Depending on the energy of the radiated particles, radiation is frequently categorized as ionizing or non-ionizing. More than 10 eV of ionizing radiation can ionize atoms and molecules and also break chemical bonds. Due to the significant differences in how harmful they are to living things, this is a crucial distinction. The radioactive materials that produce helium nuclei, electrons or positrons, and photons, respectively, are a common source of ionizing radiation. Secondary cosmic rays, which are produced when primary cosmic rays interact with the earth’s atmosphere and are made up of muons, positrons, neutrons, mesons, and other particles, are two additional sources. The ionizing portion of the electromagnetic spectrum is made up of X-rays, Gamma-rays, and ultraviolet light with higher energy levels. The process of breaking one or more electrons away from an atom, which requires the relatively high energies that these electromagnetic waves provide, is referred to as “ionizing.”

The non-ionizing lower energies of the lower ultraviolet spectrum further down the spectrum cannot ionize atoms but can break down molecules rather than atoms by disrupting the inter-atomic bonds that make up molecules. An excellent illustration of this is sunburn caused by long-wavelength solar ultraviolet. Waves with a longer wavelength than UV can be seen as light, infrared and microwave frequencies can cause vibrations in bonds that are detected as heat, but they cannot break bonds. In most cases, biological systems are not thought to be harmed by radio waves below certain wavelengths. There is some overlap in the effects of particular frequencies, and these are not precise energy delineations [2]. Radiation exposure is harmful to both the mother and her unborn child during pregnancy. Ionizing radiation exposure during pregnancy can vary greatly, from low-dose/dose-rate exposures like diagnostic radiography to extremely high-dose/dose-rate exposures like the Hiroshima and Nagasaki bombings. When assessing the risk, additional factors, such as the timing of exposure (in relation to the gestational age of the developing offspring), the type of radiation, and the route of exposure, must also be measured. The possibility of long-term effects on children as a result of prenatal radiation exposure is an emerging area of concern. The idea of developmental programming is supported by substantial evidence. The alteration in the phenotype or bodily processes of the offspring as a result of an injury sustained in utero [3,4].

The idea of developmental programming centers around the mother experiencing stress and the developing fetus challenging to adapt to the stress due to moving across the placenta [5] despite the fact that a variety of triggers have been identified, such as the exposure of an external stressor to the mother (such as hypoxia) or poor intrauterine environment (such as malnutrition).

Effects of Ionizing Radiation

The study of atomic bomb survivors who were exposed to high doses of radiation while in utero in Nagasaki and Hiroshima, both in Japan, has contributed significantly to our understanding of the effects of radiation on humans [6]. There is a dose threshold below which clinically apparent effects cannot be observed for ionizing radiation, which can result in deterministic effects. The serious impact of high portion is edge [5,7]. There are fatal consequences, such as miscarriage and decreased cell division (restriction of fetal growth); microcephaly, mental harm, and teratogenic effects (fetal malformation) On the other hand, the probability of causing damage to a single cell in a tissue, for which there is thought to be no dose threshold, is the source of stochastic effects caused by radiation. These impacts incorporate mutogenic and cancer-causing impact. The stage of pregnancy is connected to all of these effects. The changes that occur in the central nervous system are the most common teratogenic effects of high dose radiation. At 10 weeks of pregnancy, high exposure increases the risk of microcephaly and severe mental retardation.

The factors related to maternal uptake and excretion of the radiopharmaceutical, the agent’s passage across the placenta, and uptake in the conceptus determine the variable dose to the conceptus from radionuclide examinations. The developing fetus may be harmed by radiotherapy during pregnancy. In most cases, pregnant women with cancer are advised to postpone receiving radiotherapy until after giving birth. The expected effects of radiation, such as mental retardation and organ malformations, are most likely to occur only above a threshold dose of 0.1-0.2 Gy [8].

If the tumors are sufficiently far from the fetus and measures have been taken to shield the unborn child from leakage radiation and collimator scatter from the teletherapy machine, healing radiotherapy during pregnancy typically does not reach this threshold dose; Additionally, radiation-induced childhood cancer and leukemia in the unborn are less likely with this protection. The Roentgen (R) is the unit of this first measurement, which is called exposure. It is possible to calculate the energy absorbed by tissue once the exposure and nature of the radiation beam are known. According to the pharmacological concept of concentration [9], this quantity is referred to as the absorbed dose and is expressed in terms of the energy absorbed per gram of tissue.

Conclusion

It is concluded that the radiation dose and gestational age largely determine the health effects of radiation exposure on a fetus. Radiation exposure to the fetus may increase the likelihood of the offspring developing cancer and other diseases, particularly at doses greater than 0.1 Gy, which are significantly higher than the typical doses received in diagnostic radiology. Due to the well-known adverse effects of high doses, low-dose radiation exposure during pregnancy is frequently a cause for concern in humans. When assessing the risk to the fetus, it is important to take into account that the majority of medical exposures in humans are low-dose exposures, and that their effects are mostly related to the developmental program. Other changes in the phenotype of the offspring are also important considerations. As the cohort ages, the lifespan study of Japanese A-bomb survivors continues. A deeper comprehension of the lifetime risk of cancer and other diseases posed by prenatal and early childhood radiation exposure should emerge from subsequent data analyses.

Acknowledgement

None

Conflict of Interest

None

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