Assessment of fetal radiation exposure in pregnant women undergoing computed tomography and rotational angiography examinations for pelvic trauma.

This study aimed to assess fetal radiation exposure in pregnant women undergoing computed tomography (CT) and rotational angiography (RA) examinations for the diagnosis of pelvic trauma. In addition, this study aimed to compare the dose distributions between the two examinations. Surface and average fetal doses were estimated during CT and RA examinations using a pregnant phantom model and real-time dosemeters. The pregnant model phantom was constructed using an anthropomorphic phantom, and a custom-made abdominal phantom was used to simulate pregnancy. The total average fetal dose received by pregnant women from both CT scans (plain, arterial and equilibrium phases) and a single RA examination was ~60 mGy. Because unnecessary repetition of radiographic examinations, such as CT or conventional 2D angiography can increase the radiation risk, the irradiation range should be limited, if necessary, to reduce overall radiation exposure.

The role of curcumin during pregnancy on the exposed fetuses' tissues of Wistar rats to electromagnetic field.

To investigate curcumin (CUR) as the protector against the harmful effects of low-frequency electromagnetic field(LF- EMF, 50 Hz) during pregnancy period, 5 males and 15 females of Wistar rat mated and vaginal plaques were observed. Then, the pregnant rats were divided into six groups. During pregnancy(21 days), the EMF group was exposed to EMF for 30 min/day, the CUR group received a single dose of 50 mg/kg/daily CUR intraperitoneal, the EMF+CUR group was injected CUR and exposed to EMF daily. The DMSO(dimethyl sulfoxide) group was injected solvent of CUR (DMSO) intraperitoneal with the same volume of CUR solvent, the sham group was placed through the solenoid in the same conditions as the first group without exposure and the control group was kept in their cage in normal condition. After four weeks, babies born were divided according to the mother groups and sacrificed. Then, the three tissues injuries were investigated. EMF exposure led to an increase in outstanding necrotic areas in hippocampal tissue, an increase in the amount of hyperemia(p = 0.017) and necrotic(p = 0.005) in kidneys, and degeneration in liver tissue(p = 0.007) in the EMF group compared with EMF+CUR groups. A single dose of CUR daily during pregnancy can protect these tissues from injuries caused by LF-EMF exposure in rat fetuses.

Electromagnetic fields (EMFs) are able to penetrate and be absorbed by the body. The researchers showed that these radiations might be harmful and lead to cancers, cardiovascular diseases, mental disorders, and fetal abnormalities. Curcumin as an active component in turmeric has anti-inflammatory, antioxidant and anti-hyperlipidemia properties. It can protect the body against diseases such as arthritis, anxiety, and metabolic syndrome. This study examined the effects of curcumin as the protector against the harmful effects of EMF (50Hz) during pregnancy period. So the pregnant rats were divided into six groups. During pregnancy, a group was exposed to EMF for 30 min/day, the second group was injected a dose of curcumin 50mg/kg/daily, the third group was injected curcumin and exposed to EMF daily. The fourth group was injected a curcumin solvent dose, the sham group was placed through the field generator in the same conditions as the first group without exposure and the control group was kept in their cage in normal condition. After four weeks, babies born were divided according to the mother groups and sacrificed. Then, the liver, kidney, and hippocampal tissues were investigated. EMF exposure led to an outstanding increase in necrotic areas in hippocampal tissue, a notable increase in the amount of hyperemia and necrosis in kidneys, and degeneration in liver tissue(p=0.007) in the EMF group compared with the third group that was exposed to EMF and received curcumin. A single dose of curcumin daily during pregnancy can protect these tissues from injuries caused by EMF(50Hz) exposure in rat fetuses.

Radiation oncology department policy development for patients who may become pregnant.

In the context of radiation oncology, radiation exposure from radiation therapy simulation, image guidance, and radiation therapy procedures can have severe adverse biological effects on a developing embryo or fetus. Patients who may be pregnant are screened for the possibility of pregnancy to prevent unnecessary or excessive exposure of radiation in utero. Some radiation therapy patients for whom a pregnancy test is indicated may elect to decline the test. In addition, some patients who are found upon screening to be pregnant may decide, with their attending radiation oncologist, to continue with treatment. A radiation oncology department policy was developed to provide guidelines regarding screening and consent. The policy was designed to prevent unnecessary exposure to patients who may be pregnant, and to limit dose to the embryo or fetus in patients for whom treatment is medically indicated. The policy is presented as an example for physicists intending to develop or revise their own practice's policy regarding patients who may become pregnant.

Fetal and Maternal Atomic Bomb Survivor Dosimetry Using the J45 Pregnant Female Phantom Series: Considerations of the Kneeling and Lying Posture with Comparisons to the DS02 System.

ABSTRACT: Organ dosimetry data of the atomic bomb survivors and the resulting cancer risk models derived from these data are currently assessed within the DS02 dosimetry system developed through the Joint US-Japan Dosimetry Working Group. In DS02, the anatomical survivor models are limited to three hermaphroditic stylized phantoms-an adult (55 kg), a child (19.8 kg), and an infant (9.7 kg)-that were originally designed for the preceding DS86 dosimetry system. As such, organ doses needed for assessment of in-utero cancer risks to the fetus have continued to rely upon the use of the uterine wall in the adult non-pregnant stylized phantom as the dose surrogate for all fetal organs regardless of gestational age. To address these limitations, the Radiation Effects Research Foundation (RERF) Working Group on Organ Dose (WGOD) has established the J45 (Japan 1945) series of high-resolution voxel phantoms, which were derived from the UF/NCI series of hybrid phantoms and scaled to match mid-1940s Japanese body morphometries. The series includes male and female phantoms-newborn to adult-and four pregnant female phantoms at gestational ages of 8, 15, 25, and 38 wk post-conception. In previous studies, we have reported organ dose differences between those reported by the DS02 system and those computed by the WGOD using 3D Monte Carlo radiation transport simulations of atomic bomb gamma-ray and neutron fields for the J45 phantoms series in their traditional "standing" posture, with some variations in their facing direction relative to the bomb hypocenter. In this present study, we present the J45 pregnant female phantoms in both a "kneeling" and "lying" posture and assess the dosimetric impact of these more anatomically realistic survivor models in comparison to current organ doses given by the DS02 system. For the kneeling phantoms facing the bomb hypocenter, organ doses from bomb source photon spectra were shown to be overestimated by the DS02 system by up to a factor of 1.45 for certain fetal organs and up to a factor of 1.17 for maternal organs. For lying phantoms with their feet in the direction of the hypocenter, fetal organ doses from bomb source photon spectra were underestimated by the DS02 system by factors as low as 0.77, while maternal organ doses were overestimated by up to a factor of 1.38. Organs doses from neutron contributions to the radiation fields exhibited an increasing overestimation by the DS02 stylized phantoms as gestational age increased. These discrepancies are most evident in fetal organs that are more posterior within the mother's womb, such as the fetal brain. Further analysis revealed that comparison of these postures to the original standing posture indicate significant dose differences for both maternal and fetal organ doses depending on the type of irradiation. Results from this study highlight the degree to which the existing DS02 system can differ from organ dosimetry based upon 3D radiation transport simulations using more anatomically realistic models of those survivors exposed during pregnancy.

Effects of ionizing radiation exposure during pregnancy.

PURPOSE: To review the effects of ionizing radiation to the conceptus and the relationship to the timing of the exposure during pregnancy. To consider strategies that would mitigate potential harms associated with exposure to ionizing radiation during pregnancy. METHODS: Data reported in the peer-reviewed literature on entrance KERMA received from specific radiological examinations were combined with published results from experiment or Monte Carlo modeling of tissue and organ doses per entrance KERMA to estimate total doses that could be received from specific procedures. Data reported in the peer-reviewed literature on dose mitigation strategies, best practices for shielding, consent, counseling and emerging technologies were reviewed. RESULTS: For procedures utilizing ionizing radiation for which the conceptus is not included in the primary radiation beam, typical doses are well below the threshold for causing tissue reactions and the risk of induction of childhood cancer is low. For procedures that include the conceptus in the primary radiation field, longer fluoroscopic interventional procedures or multiphase/multiple exposures potentially could approach or exceed thresholds for tissue reactions and the risk of cancer induction must be weighed against the expected risk/benefit of performing (or not) the imaging examination. Gonadal shielding is no longer considered best practice. Emerging technologies such as whole-body DWI/MRI, dual-energy CT and ultralow dose studies are gaining importance for overall dose reduction strategies. CONCLUSION: The ALARA principle, considering potential benefits and risks should be followed with respect to the use of ionizing radiation. Nevertheless, as Wieseler et al. (2010) state, "no examination should be withheld when an important clinical diagnosis is under consideration." Best practices require updates on current available technologies and guidelines.

Cancer in pregnancy: treatment effects.

PURPOSE: Pregnant patients present a unique challenge to cancer therapy. Due to the potential catastrophic implications related to teratogenic effects or pregnancy loss, oncologic management of this vulnerable patient group must be strategic and personalized. METHODS: This article will discuss the unique treatment approach to the pregnant cancer patient. This includes discussion of the role of imaging during staging, treatment, and follow-up with an emphasis on avoiding ionizing radiation when possible. RESULTS AND CONCLUSION: Specific considerations and modifications to standard cancer treatments, including surgery and systemic therapies such as chemotherapy, immunotherapy, targeted and hormone therapies are crucial components of providing oncologic care to minimize negative effects to the mother and developing fetus. Radiation and proton therapy are also options that may be employed in specific circumstances. Finally, this article will address the long-term treatment effects of these therapies on future fertility.

Translocations are induced in hematopoietic stem cells after irradiation of fetal mice.

Although mammalian fetuses have been suggested to be sensitive to radiation, an increased frequency of translocations was not observed in blood lymphocytes from atomic bomb (A-bomb) survivors who were exposed to the bomb in utero and examined as adults. Since experiments using hematopoietic cells of mice and rats confirmed this finding, it was hypothesized that either irradiated fetal hematopoietic stem cells (f-HSCs) cannot generate exchange-type chromosomal aberrations or cells bearing induced aberrations are eliminated before the animals reach adulthood. In the present study, pregnant mice (12.5-15.5 days post coitum [dpc]) were irradiated with 2 Gy of X-rays and long-term HSCs (LT-HSCs) were isolated 24 h later. Multicolor fluorescence in situ hybridization (mFISH) analysis of LT-HSC clones proliferated in vitro showed that nine out of 43 (21%) clones from fetuses and 21 out of 41 (51%) clones from mothers bore translocations. These results indicate that cells with translocations can arise in mouse f-HSCs but exist at a lower frequency than in the mothers 24 h after X-ray exposure. Thus, it seems likely that translocation-bearing f-HSCs are generated but subsequently disappear, so that the frequency of lymphocyte translocations may decrease and reach the control level by the time the animals reach adulthood.

A review on fetal dose in Radiotherapy: A historical to contemporary perspective.

This paper aims to review on fetal dose in radiotherapy and extends and updates on a previous work1 to include proton therapy. Out-of-field doses, which are the doses received by regions outside of the treatment field, are unavoidable regardless of the treatment modalities used during radiotherapy. In the case of pregnant patients, fetal dose is a major concern as it has long been recognized that fetuses exposed to radiation have a higher probability of suffering from adverse effects such as anatomical malformations and even fetal death, especially when the 0.1Gy threshold is exceeded. In spite of the low occurrence of cancer during pregnancy, the radiotherapy team should be equipped with the necessary knowledge to deal with fetal dose. This is crucial so as to ensure that the fetus is adequately protected while not compromising the patient treatment outcomes. In this review paper, various aspects of fetal dose will be discussed ranging from biological, clinical to the physics aspects. Other than fetal dose resulting from conventional photon therapy, this paper will also extend the discussion to modern treatment modalities and techniques, namely proton therapy and image-guided radiotherapy, all of which have seen a significant increase in use in current radiotherapy. This review is expected to provide readers with a comprehensive understanding of fetal dose in radiotherapy, and to be fully aware of the steps to be taken in providing radiotherapy for pregnant patients.

A historical review of the effects of dental radiography on pregnant patients.

BACKGROUND: The safety of dental radiography performed on pregnant patients has been a controversial topic since the 1960s. This review synthesizes and consolidates findings, from 1957 through 2021, of the effects dental ionizing radiation could have on a pregnant patient and in utero birth defects. TYPES OF STUDIES REVIEWED: Using PubMed, the following key words were searched: pregnancy, radiology, radiograph, radiation dose, fetus, x-ray, and dental. Criteria evaluation was done on the basis of availability, completeness, quality, relevance, technicality (that is, dental radiography), topicality (that is, pregnant patients), and usability. These results were then filtered on the basis of quantitative and qualitative data as well as the period (decades within the historical framework). The final selection of relevant literature consisted of various studies including cohort studies, systematic reviews, meta-analyses, case reports, and other narrative reviews. RESULTS: If properly performed, the amount of ionizing radiation produced during dental radiographic procedures is so low that it is unlikely to reach the teratogenic threshold. Thus, dental ionizing radiation is unlikely to cause in utero birth defects because it has been detected to have a deterministic (not stochastic) effect. With this information and historical context, this article shows that necessary dental radiography is safe at any stage during pregnancy, as long as proper safety equipment is appropriately used. CONCLUSIONS AND PRACTICAL IMPLICATIONS: As technology advances, more research can further clarify ionizing radiation safety for pregnant patients and its potential effects on in utero birth defects, improving overall oral health care. The dental community must remain educated about current ionizing radiation safety guidelines to make better-informed decisions and successfully provide proper oral health care to pregnant patients.

[Which imaging methods are safe in pregnant patients? A step-by-step plan to choose the right method]. / Welk beeldvormend onderzoek bij een zwangere patiënt?

Diagnostic imaging in pregnant patients often causes worries about radiation effects and IV contrast. We use a step-by-step plan to choose the right method and illustrate this with a case. First, we choose the method of imaging, non-ionizing imaging being preferred over ionizing. With ionizing radiation, the fetal dose is limited as much as possible with teratogenic and carcinogenic risk as low as possible (as low as reasonably achievable (ALARA)). The second consideration is whether intravenous contrast medium is necessary. The risks of the imaging procedure for the fetus (and patient) are compared with the risks for the patient (and fetus) without imaging. Furthermore, possible treatment changes are important. Finally, the patient is informed about the procedure, the necessity of it and possible negative effects for the fetus and patient. In our case these risks were minimal and it was not necessary to explicitly discuss them with the patient.

Radiotherapy and pregnancy.

We present the updated recommendations of the French society for radiation oncology on radiotherapy and pregnancy. The occurrence of cancer during pregnancy is a rare event (approximately 1 in 1000 pregnancies). The risks for the embryo or the foetus depend on the gestational age at the time of irradiation. The main risks are malformations with microcephaly and mental retardation. There is also a risk of radiation-induced cancer in the unborn child. In the case of only supradiaphragmatic irradiation, radiotherapy can be performed most often in pregnant women without risk to the foetus. On the other hand, in the case of an indication for subdiaphragmatic irradiation, therapeutic termination of the pregnancy should be proposed. In all cases, when radiotherapy is chosen, a phantom estimation of the dose delivered to the foetus, confirmed by in vivo measurement, is recommended. Conformational radiotherapy is the preferred technique because of the lower dose delivered to the foetus (except in tumour locations where other techniques such as IMRT are recommended).

THYROID SCREENING AND RELIABILITY OF RADIATION THYROID DOSES FOR THE BELARUSIAN IN UTERO COHORT.

OBJECTIVE: To describe the status and results of thyroid disease screening and assessment of reliability of radiationthyroid doses in the Belarusian in utero cohort of 2,965 individuals exposed to Chernobyl (Chornobyl) fallout. MATERIALS AND METHODS: Thyroid screening examinations are currently underway including thyroid palpation by anendocrinologist, ultrasonographic examination by an ultrasonographer and analysis of blood samples for diagnosisof hypo- and hyperthyroidism, autoimmune thyroiditis, thyroid function tests (thyroid-stimulating hormone [TSH],thyroxine [T4], thyroid peroxidase antibody [anti-TPO], and thyroglobulin antibodies [anti-TG]). Reliability of (i)information from 780 pairs of questionnaires obtained during the first and second interviews of the mothers and (ii)thyroid doses, which were calculated for the cohort members using this information, is evaluated. RESULTS: As of 15 August 2021, 1,267 in utero exposed study subjects had been screened. A single thyroid nodule wasdiagnosed in 167 persons (13.2 % of the total) and multiple thyroid nodules in 101 persons (8.0 %): 189 (14.9 %)persons had nodules detected for the first time at the screening while 79 (6.2 %) persons had nodules detected pre-viously (pre-screening nodules). Fifty-nine out of 268 subjects (22.0 %) with a suspicious thyroid nodule werereferred to fine needle aspiration biopsy, and among them 33 (55.9 %) were biopsied. Reasonable agreement wasobserved for modelqbased doses calculated for the Belarusian in utero cohort members using data from the two inter-views (Spearman's rank-correlation coefficient rs = 0.74, p < 0.001), while measurementqbased doses yielded almost per-fect agreement (rs = 0.99, p < 0.001). CONCLUSIONS: During the thyroid screening, at least one thyroid nodule was identified in 268 of 1,267 (21.2 %) inutero exposed cohort members. Seven thyroid cancer cases were identified in the cohort, including 5 pre-screeningcases and 2 cases detected during the screening. Ongoing research on this unique cohort will provide importantinformation on adverse health effects following prenatal and postnatal exposure to radioiodine and radiocesium iso-topes, for which available epidemiological data are scant.

Trichostatin A mitigates radiation-induced teratogenesis in C57Bl/6 mice.

Radiation exposure in utero is known to lead to serious concerns to both the mother and children, including developmental anomalies in the children. In the recent past, trichostatin A, an HDAC (histone deacetylase) inhibitor and epigenetic modifier, has been shown to mitigate radiation-induced anomalies in the male reproductive system of C57BL/6 mice. Therefore, the current study was undertaken to evaluate the mitigating effects of trichostatin A (TSA) against radiation-induced developmental anomalies in mice. Foetuses of in utero whole-body gamma-irradiated mice during the active organogenesis period were examined for developmental anomalies at 8.5 and 18.5 days of gestation. In utero radiation exposure caused developmental anomalies like microcephaly, microphthalmia, gastroschisis and kinky tail besides prenatal mortality. TSA administration post-irradiation was observed to reduce 50% of prenatal mortality at E18.5 by reducing congenital and developmental anomalies. Observation of such results could be corroborated with the HDAC inhibitory potential of TSA knowing that developmental anomalies may have epigenetic origin. TSA, therefore, can be considered as a potential radiomitigator.

Evaluation of a new foetal shielding device for pregnant brain tumour patients.

BACKGROUND: The present study aimed to propose a new foetal shielding device for pregnant cancer patients to reduce the foetal dose associated with treatment techniques using multiple gantry angles, such as intensity-modulated radiation therapy (IMRT) or volumetric modulated arc therapy (VMAT). METHODS: Three shielding structures were designed to minimise the scattered and leaked radiation from various gantry angles and radiation scattering within the patient. The base-plate part that can be placed on the treatment couch was designed to reduce the scattered and leaked radiation generated at gantry angles located near 180°. A body shielding part that can cover the lower chest and abdomen was designed, and a neck-shielding structure was added to reduce the internal and external radiation scattering from the treatment area. Evaluation plans were generated to assess the foetal dose reduction by the foetal shielding device in terms of the shielding material thickness, distance from the field edge, and shielding component using the flattened 6 MV photon beam (6MV) and flattening filter-free 6 MV photon beam (6MV-FFF). In addition, the effectiveness of the foetal shielding device was evaluated in a pregnant brain tumour patient. RESULTS: The shielding material consisting of three parts was placed on frames composed of four arch shapes with a vertical curved structure, connection bar at the top position, and base plate. Each shielding part resulted in reductions in the radiation dose according to the treatment technique, as the thickness of the shielding material increased and the foetal dose decreased. In addition, a foetal dose reduction of approximately 50% was confirmed at 50 cm from the field edge by using the designed shielding device in most delivery techniques. In patients, the newly designed shielding structures can effectively eliminate up to about 49% of the foetal dose generated from various gantry angles used in VMAT or IMRT. CONCLUSIONS: We designed a foetal shielding device consisting of three parts to effectively reduce the dose delivered to the foetus, and evaluated the device with various treatment techniques for a pregnant patient with brain tumour. The foetal shielding device shielded the scattered/leaked radiation from the treatment machine, and also effectively reduced internal scattering from the treatment area in the patient.

Effect of Bone Marrow Transplantation on the Fetal Skeleton of Maternally Irradiated Pregnant Rats.

BACKGROUND AND OBJECTIVE: Prenatal exposure to ionizing radiation can interfere with embryonic and fetal growth depending on the dose and gestational age. The present study was completed to evaluate the effect of transplanted bone marrow on the fetal skeleton of pregnant rats exposed to gamma radiation. MATERIALS AND METHODS: Experimental animals were separated into 5 groups: C group, R7 group, R7+BM group, R14 group and R14+BM group. All pregnant rats were sacrificed on day 20 days of gestation and the skeletal systems of the fetuses were examined and photographed. This study focused on skull, upper and lower jaw, occipital region, sacral and caudal region, fore and hind limbs. RESULTS: Gamma rays caused any disturbance in the ossification process of the skull bones, upper and lower jaws, occipital bones, it caused the loss of some ossification centers in metacarpal bones, metatarsal bones but bone marrow transplantation greatly reduced the injury that happened because of γ-radiation. CONCLUSION: This study showed that transplantation of bone marrow post-irradiation in pregnant rats could reduce the hazards of gamma-irradiation in the different regions of the fetal skeleton.

Organ doses of the fetus from external environmental exposures.

This article presents nuclide-specific organ dose rate coefficients for environmental external exposures due to soil contamination assumed as a planar source at a depth of 0.5 g cm-2 in the soil and submersion to contaminated air, for a pregnant female and its fetus at the 24th week of gestation. Furthermore, air kerma free-in-air coefficient rates are listed. The coefficients relate the organ equivalent dose rates (Sv s-1) to the activity concentration of environmental sources, in Bq m-2 or Bq m-3, allowing to time-integrate over a particular exposure period. The environmental radiation fields were simulated with the Monte Carlo radiation transport codes PHITS and YURI. Monoenergetic organ dose rate coefficients were calculated employing the Monte Carlo code EGSnrc simulating the photon transport in the voxel phantom of a pregnant female and fetus. Photons of initial energies of 0.015-10 MeV were considered including bremsstrahlung. By folding the monoenergetic dose coefficients with the nuclide decay data, nuclide-specific organ doses were obtained. The results of this work can be employed for estimating the doses from external exposures to pregnant women and their fetus, until more precise data are available which include coefficients obtained for phantoms at different stages of pregnancy.

Repeated electromagnetic field stimulation lowers amyloid-ß peptide levels in primary human mixed brain tissue cultures.

Late Onset Alzheimer's Disease is the most common cause of dementia, characterized by extracellular deposition of plaques primarily of amyloid-ß (Aß) peptide and tangles primarily of hyperphosphorylated tau protein. We present data to suggest a noninvasive strategy to decrease potentially toxic Aß levels, using repeated electromagnetic field stimulation (REMFS) in primary human brain (PHB) cultures. We examined effects of REMFS on Aß levels (Aß40 and Aß42, that are 40 or 42 amino acid residues in length, respectively) in PHB cultures at different frequencies, powers, and specific absorption rates (SAR). PHB cultures at day in vitro 7 (DIV7) treated with 64 MHz, and 1 hour daily for 14 days (DIV 21) had significantly reduced levels of secreted Aß40 (p = 001) and Aß42 (p = 0.029) peptides, compared to untreated cultures. PHB cultures (DIV7) treated at 64 MHz, for 1 or 2 hour during 14 days also produced significantly lower Aß levels. PHB cultures (DIV28) treated with 64 MHz 1 hour/day during 4 or 8 days produced a similar significant reduction in Aß40 levels. 0.4 W/kg was the minimum SAR required to produce a biological effect. Exposure did not result in cellular toxicity nor significant changes in secreted Aß precursor protein-α (sAPPα) levels, suggesting the decrease in Aß did not likely result from redirection toward the α-secretase pathway. EMF frequency and power used in our work is utilized in human magnetic resonance imaging (MRI, thus suggesting REMFS can be further developed in clinical settings to modulate Aß deposition.

What information did pregnant women want related to risks and benefits attending X-ray examinations?

BACKGROUND: In connection with X-ray examinations of pregnant patients, good communication of benefit and risk is important to provide adequate patient care. Pregnant women often become concerned about the foetus and are unsure of the risk of malformations and the development of cancer. Health professionals who are involved in imaging pregnant women require specif knowledge about risks and benefits so they can convey information without creating unnecessary fear. PURPOSE: This study identifies the information needs of pregnant women in connection with X-ray examinations and how they prefer to have the information communicated. METHOD: A qualitative study using semi-structured interviews of seven pregnant women aged 28-36 in weeks 16-33 of their pregnancy. The interviews were analysed using interpretive phenomenological analysis. RESULTS: The participants had expectations regarding the information provided about X-ray examinations during pregnancy. They needed concrete information on radiation doses, risks and any effects on the foetus. The risk was thought to be low, but several of the participants would still have been concerned when undergoing an X-ray examination. CONCLUSION: To provide adequate care of pregnant women in connection with X-ray examinations, healthcare professionals must have knowledge of pregnancy and radiation and have expertise in risk communication. This will prevent unnecessary concern in the pregnant woman, ensure that justified necessary examinations are carried out, and avoid adverse decisions such as termination of pregnancy based on erroneous grounds.

Mortality among individuals exposed to atomic bomb radiation in utero: 1950-2012.

We examined the mortality risks among 2463 individuals who were exposed in utero to atomic bomb radiation in Hiroshima or Nagasaki in August 1945 and were followed from October 1950 through 2012. Individual estimates of mother's weighted absorbed uterine dose (DS02R1) were used. Poisson regression method was used to estimate the radiation-associated excess relative risk per Gy (ERR/Gy) and 95% confidence intervals (CI) for cause-specific mortality. Head size, birth weight, and parents' survival status were evaluated as potential mediators of radiation effect. There were 339 deaths (216 males and 123 females) including deaths from solid cancer (n = 137), lymphohematopoietic cancer (n = 8), noncancer disease (n = 134), external cause (n = 56), and unknown cause (n = 4). Among males, the unadjusted ERR/Gy (95% CI) was increased for noncancer disease mortality (1.22, 0.10-3.14), but not for solid cancer mortality (- 0.18, < - 0.77-0.95); the unadjusted ERR/Gy for external cause mortality was not statistically significant (0.28, < - 0.60-2.36). Among females, the unadjusted ERRs/Gy were increased for solid cancer (2.24, 0.44-5.58), noncancer (2.86, 0.56-7.64), and external cause mortality (2.57, 0.20-9.19). The ERRs/Gy adjusted for potential mediators did not change appreciably for solid cancer mortality, but decreased notably for noncancer mortality (0.39, < - 0.43-1.91 for males; 1.48, - 0.046-4.55 for females) and external cause mortality (0.10, < - 0.57-1.96 for males; 1.38, < - 0.46-5.95 for females). In conclusion, antenatal radiation exposure is a consistent risk factor for increased solid cancer mortality among females, but not among males. The effect of exposure to atomic bomb radiation on noncancer disease and external cause mortality among individuals exposed in utero was mediated through small head size, low birth weight, and parental loss.

Thyroid Doses to French Polynesians Resulting from Atmospheric Nuclear Weapons Tests: Estimates Based on Radiation Measurements and Population Lifestyle Data.

Thyroid doses were estimated for the subjects of a population-based case-control study of thyroid cancer in a population exposed to fallout after atmospheric nuclear weapons tests conducted in French Polynesia between 1966 and 1974. Thyroid doses due to (1) intake of I and of short-lived radioiodine isotopes (I, I, I) and Te, (2) external irradiation from gamma-emitting radionuclides deposited on the ground, and (3) ingestion of long-lived Cs with foodstuffs were reconstructed for each study subject. The dosimetry model that had been used in 2008 in Phase I of the study was substantially improved with (1) results of radiation monitoring of the environment and foodstuffs, which became available in 2013 for public access, and (2) historical data on population lifestyle related to the period of the tests, which were collected in 2016-2017 using focus-group discussions and key informant interviews. The mean thyroid dose among the study subjects was found to be around 5 mGy while the highest dose was estimated to be around 36 mGy. Doses from I intake ranged up to 27 mGy, while those from intake of short-lived iodine isotopes (I, I, I) and Te ranged up to 14 mGy. Thyroid doses from external exposure ranged up to 6 mGy, and those from internal exposure due to Cs ingestion did not exceed 1 mGy. Intake of I was found to be the main pathway for thyroid exposure accounting for 72% of the total dose. Results of this study are being used to evaluate the risk of thyroid cancer among the subjects of the epidemiologic study of thyroid cancer among French Polynesians.