Effects of Radiation Exposure on the Developing Fetus Hannah Connolly, Janessa Gioia, Gillian Reid, Nadine Savoie, Suzanne Taylor University of New Brunswick

Problem Statement  Pregnant women may be denied diagnostic and therapeutic radiation procedures because physicians fear the radiation will cause harm to the developing fetus. Thus, fewer options are available for improving the health of pregnant women when they require medical attention. Understanding the effects of radiation on the developing fetus may help physicians better counsel their patients on the risks involved. This education would allow for an informed decision to be made on whether to proceed with radiation procedures. Retrieve from

Research Question  Are diagnostic and therapeutic radiation procedures harmful to the developing fetus? Retrieve from

Harmful  Teratogenic- causing congenital malformations  Carcinogenic- cancer causing  Mutagenic- causing genetic changes (Whitt, 2010) Retrieve fromhttp:// d_Repair_Antibodies Retrieve from Retrieve from feed:// 22/posts/default

Related Diseases  Major Mutations  Other abnormalities  The major risk is of course, embryonic loss. (Brent 1999). Retrieve from

Radiation: DNA Damage Retrieve from

History of why these studies emerged  Hiroshima and Nagasaki, Chernobyl  In 1956: prenatal exposure to radiation from diagnostic X-ray (Naumburg et al. 2001; Doll & Wakeford, 1997) Retrieve fromhttp://awesometalks.files.wordpress.com/2008/08/ng30.jpgRetrieve from

Fetal Stages and Radiation Sensitivity  (1) Preimplantation (days 0 to ~14)  (2) Organogenesis (week 2 to week 8)  (3) Fetal (week 9 to term) Retrieved from: _sys.shtml Retrieve from organogenesis Retrieve from development

Methods  Quantitative  Experimental  Non Experimental  Retrospective  Prospective  Surveys  Time frames  Longitudinal Retrieve from

Health Concerns  From our studies these are some health concerns that would bring pregnant woman to our departments  Pulmonary Embolism  Loss of bone density  Cancer  Abdominal/Pelvic issues Retrieve from

Pulmonary Embolism Retrieve from

Pulmonary Embolism  Chest X-ray + V-P Scan + Helical CT + Pulmonary Angiograpy with brachial approach = ~ 1000 uGy.  Ventilation perfusion scans:  The presence and absence of PE is inconclusive in up to 80% of these scans  Prior episodes of PE may cause a false-positive result (Winner-Muram et al., 2002)  Fetal dose > 10 cGy, the probability of congenital defects rises 10%. (Tutty, 2001) Retrieved from:

Bone Density  There is evidence that some pre-existing disorders as well as heparin treatments may lead to significant diminution of bone mass during pregnancy.  Treatment would be administered to patients who demonstrate rapid bone lose during the first postconception months.  Emryo/fetus doses were found to be lower than the average daily natural background from a proximal femur scan.  Benefits Outweigh Risks! (Damilakis, 2002) Retrieve from

Abdominal and Pelvic Procedures  Medical imaging such as CT may be required of the abdominal/trunk/pelvic area due to trauma, acute abdominal pain, appendicitis, or renal issues in a pregnant patient.  Ultrasound  Survey respondents are more likely to choose CT for trauma in all three trimesters.  For acute abdominal indications they were more likely to choose CT in the second and third trimester, and MRI in the first trimester.  The trend found in radiology literature is that CT is fast, readily available and allows immediate surgical intervention if needed. (Jaffe, 2007) Retrieve from ogy/presentations/radiology/slide25.htm Retrieve from nal_radiology/presentations/radiology/slide25htm

Abdominal and Pelvic Procedures  Literature suggests that for most radiologic procedures, the risk of fetal demise in the first 2 weeks after conception is less than 1% (Jaffe, 2007).  Radiologists may also opt for a modified CT protocol to reduce the exposure by reducing the power of the x-rays (kVp or mAs) (Damilakis et al., 2000).  No direct radiation to the fetus. (Hurtwitz et al. 2006; Kal & Struikmans, 2005) Retrieved from content/uploads/2010/10/CT- Scan.jpg

Cancer Diagnosis & Treatment when Pregnant  Cancer: 1 per 1000 pregnancies (Kal & Struikmans, 2005; Pavlidis & Penteroudakis, 2005)  Most common cancer types (Greskovich & Macklis, 2000; Pavlidis & Penteroudakis, 2005).  Carcinoma of the cervix: is the most common  Breast cancer pregnant patient 1 in 3000 (Berry et al. 1999; Greskovich & Macklis, 2000; Kal & Struikmans, 2005; Pandit-Taskar et al. 2006)  Radiation therapy is not usually offered during pregnancy (Pavlidis & Penteroudakis, 2005; Kal & Struikmans, 2005) Retrieve from week/ Retrieved from 0/10/pregnant-breast-cancer-330-.jpg Retrieved from content/uploads/2009/08/pregnantandcancer.jpg

Diagnosing Oncology Patients  To diagnose:  Fine-needle biopsy, ultrasound, mammography, MRI (Berry et al. 1999; Greskovich & Macklis, 2000; Pavlidis & Penteroudakis, 2005; Kal & Struikmans, 2005, Hurtwitz et al., 2006; Doll & Wakeford, 1997; Nicklas & Baker, 2000) Retrieve from pregnant-women-need-more-than-one-ultrasound/ Retrieve from archives/breast-cancer-blog/April html Retrieve from

Delaying Radiation  All chemotherapy drugs: crossing the placenta.  The first trimester: spontaneous abortion.  ethical balance must be achieved (Pavlidis & Penteroudakis, 2005; Kal & Struikmans, 2005).  Delaying treatment until the second and third trimester. (Greskovich & Macklis, 2000; Pavlidis & Penteroudakis, 2005, Doll & Wakeford, 1997; Departement of Health and Human Services, 2005). Retrieve from of-drugs-taken-during-pregnancy

Staging for Oncology Patients  The benefits vs. risks (Greskovich & Macklis, 2000; Osei & Faulkner, 2000).  Main concerns of doctors (Pavlidis & Penteroudakis, 2005).  The medical staff and patient need to decide as a team whether to begin treatment or to postpone it (Kal & Struikmans, 2005). Retrieve from

How much radiation is to much?  It is concluded that radiation doses of the order of 10 mGy received by the fetus in utero produce a consequent increase in the risk of childhood cancer. (Doll & Wakeford, 1997)  Lymphoscintigraphy for sentinel lymph node mapping (SLN) led to a neglible dose to the fetus (0.014 mGy or less) (Pandit-Taskar, 2006). Retrieve from

Retrieve from Retrieve from Retrieve from premise.com/images/products/large/aprons/claire_h ugo.jpg Oncology Studies  Relative risk are higher: first (Greskovich & Macklis, 2000; Pavlidis & Penteroudakis, 2005; Doll, & Wakeford, 1997; Department of Health and Human Services, 2005).  Mastectomy with postpartum radiation (Berry et al. 1999)  Patients received a median of four cycles of chemotherapy (Berry et al. 1999; Doll, & Wakeford, 1997; Department of Health and Human Services, 2005).  Neonates: no unusual complications or malformations. (Berry et al. 1999)  Fetal dose was much less than the NCRP limit. Pandit-Taskar et al. (2006 )

Oncology- Thyroid Cancer  Radioiodine ( 131 I) Therapy  Abnormalities  Indirect exposure to: the uterus, 131 I uptake in the blood, bladder, gut, kidneys  Within a year after the therapy: miscarriages and induced abortions.  A number of stillbirths after radioiodine therapy: high.  Thyroid hormone  DO NOT: conceive one month prior the therapy and postponing conception until the thyroid hormone status has been verified. (Garsi, J-P., et al. 2008, Bohuslavizki, 1999) Retrieve from r-abdul-azim-hussain/ Retrieve from category/thyroid-cancer/

Childhood Development  Preschool aged children  No damaging effects of diagnostic imaging, low dose x- radiation. (Ornoy et al., 1996)  Large radiation doses (Department of Health and Human Services, 2005) Retrieve from child Retrieve from

Childhood Cancer  The USNCRP: doses of 50 mGy or less is negligible  Baseline risks  However…  increases in use of of CT and nuclear medicine radiodiagnostic procedures  Inadvertent exposure in early pregnancy may occur (Ratnapalan et al., 2003; Ray et al. 2010) Reftrieve from cancer-kids-baby-with-daffodils.php Retrieve from

Childhood Cancer Leukemia  Leukemia is the most common malignancy among children.  Study: children born in Sweden between  Association between leukemia and diagnostic x-rays is likely to be small. (Naumburg et al., 2001) Retrieve from

Childhood Cancer Malignancy  Ontario study: Between April 1, 1992 and March 31,  Researchers looked at the incidence of malignancy in those children  Exposed mothers vs. unexposed mothers  They concluded: no difference noted (Ray et al., 2010) Retrieve from

Perception of the Risks  Ontario survey  Misperceptions of physicians  Could lead to anxiety, delay of care among pregnant woman (Ratnapalan et al., 2004)  Misperception of patients may be caused by misinformation (Bentur et al. 1991) Retrieve from 007/09/01-07/doctor-child.jpg Retrieve from ctorChildCheckup.jpg Retrieve from n07.jpg

Recommendations & Precautions  Menstrual Cycle (Vollman, 1977; Zanotti-Fregonara et al. 2009)  Modify daily procedures  ALARA- as low as reasonably achievable  Radiation Therapy  Do treatment planning and risk management. (Bednarz & Xu, 2008).  Lead shielding (Sechopoulos et al. 2008)   Serum testing (Ray et. al, 2010)  MRI and Ultrasonography  Bone densitometry on a pregnant patient  Physician education (Ratnapalan et al., 2004)  Brief counseling  Pregnant nuclear workers (Damilakis et al. 2005) Retrieve from business/small-business-insurance/health-insurance-options-for- the-self-employed.shtml

Retrieve from Limitations  Randomization  Small sample size  The use of phantoms instead of real-life subjects.  Phantom does not take into account all different body variation  Retrospective designs  Results are only approximations. Retrieve from

Conclusion  The amount of radiation absorbed by the fetus varies  Misperceptions exist  2 most important determining factors : dose & stage of gestation  The effects of radiation may be harmful: threshold value of 50 mGy  ALARA  Benefits outweigh risks Retrieve from

References