Article Type
Changed
Mon, 01/14/2019 - 11:16
Display Headline
What are the risks to the fetus associated with diagnostic radiation exposure during pregnancy?
EVIDENCE-BASED ANSWER

There is no evidence of significant risk to the developing fetus from any single diagnostic x-ray exposure (strength of recommendation: C, based on non-homogenous case-control studies). No studies were found on fetal exposure risks from other forms of diagnostic radiation such as computed tomography (CT) scans, fluoroscopy, or mammography. Prudent clinicians should order only those studies that result in clinically important information and efforts should be made to minimize fetal exposure.

CLINICAL COMMENTARY

Communication with the patient can go a long way to alleviate concerns regarding effects of radiation
Timothy Huber, MD
Oroville, Calif

The lack of high-quality research coupled with a general societal fear of radiation during pregnancy can create tension between the physician and the patient who needs diagnostic studies during pregnancy. This review reassures the conscientious practitioner that there is little to fear from the prudent use of routine studies. There is less clarity when a woman needs multiple or higher-dose radiation studies, especially in the first trimester.

Patients need our best estimates regarding the medical necessity, diagnostic benefit, and overall risk in these situations. Open communication with the patient can go a long way to alleviate concerns regarding the possible teratogenic or carcinogenic effects of radiation. Working more closely with our radiology colleagues to determine the best set of studies for a particular situation can help reduce the overall total radiation exposure. I refer patients who are Internet-savvy to www.familydoctor.org for more information about diagnostic radiation exposure in pregnancy.

 

Evidence summary

Clinicians have been concerned about x-ray exposure during pregnancy since the 1950s. Much of this concern was based on the Oxford Survey of Childhood Leukemia, as well as other early case-control studies.1-3 These studies reported an approximate 40% increase in the risk of childhood leukemia among offspring of women who received diagnostic x-rays in pregnancy. However, by modern standards, these studies are of poor quality as they are limited by reliance on maternal recall of prenatal x-ray exposure, lack of consideration for multiple confounding factors, lack of blinding in determination of exposure and outcome status, limitations in selection of both cases and controls, and other significant methodological flaws.

Modern, well-designed studies have failed to replicate the association between in utero radiation and childhood malignancies found in the early studies. We found 1 good-quality and 5 fair-quality case-control studies examining the association between in utero x-ray exposure and childhood leukemia, as well as 6 fair-quality case-control studies examining the association with other childhood malignancies. These studies found no significant association between in utero exposure to any x-ray in general, or to abdominal or pelvic x-rays and development of subsequent childhood leukemia, central nervous system tumors or other malignancies (TABLE).

No meta-analyses, randomized controlled trials, cohort studies or good- or fair-quality case-control studies were found examining in utero x-rays and decreased head circumference, congenital malformations, spontaneous abortion, low birth weight, or developmental problems. One recent, fair-quality case-control study found an association between prenatal dental x-rays and low birth weight (odds ratio [OR]=1.8 [95% confidence interval, 1.09–1.36]) for radiation exposures above 0.4 Gy.4 However, this study has been criticized for several reasons, including lack of biological plausibility and failure to control for dental disease.5

There does not appear to be an increased risk of adverse pregnancy outcomes with prenatal endoscopic retrograde cholangiopancreaticogram (ERCP), though this conclusion is based on 2 incomplete case series reports with no follow-up of the infants after delivery.6,7 No good- or fair-quality studies were found examining the association between other diagnostic radiation exposures (CT scan, mammography, positron emission tomography scan, dual-energy x-ray absorptiometry [DEXA]) with adverse pregnancy outcomes.

TABLE
Risk of childhood malignancy after in utero diagnostic X-ray studies1

OUTCOMETYPE OF STUDYODDS RATIO [95% CI]
Leukemia9-14Any x-ray0.8–1.8 [0.5–3.6]
Pelvic x-ray0.7–3.4 [0.4–12.9]
CNS tumor12,15Any x-ray0.78 [0.44–1.36]
Abdominal x-ray1.5 [0.5–4.2]
Any cancer12,13,16,17Any x-ray0.92–1.2 [0.47–2.4]
Abdominal x-ray1.4 [0.8–2.5]

Recommendations from others

The American College of Obstetricians and Gynecologists recommends that women be counseled that x-ray exposure from a single diagnostic procedure does not result in harmful fetal effects. Concern about possible effects of ionizing radiation exposure should not prevent medically indicated diagnostic x-ray procedures from being performed on a pregnant woman.8

References

1. Fattibene P, Mazzei F, Nuccetelli C, Risica S. Prenatal exposure to ionizing radiation: sources, effects and regulatory aspects. Acta Paediatr 1999;88:693-702.

2. Bross ID, Natarajan N. Risk of leukemia in susceptible children exposed to preconception, in utero and postnatal radiation. Prev Med 1974;3:361-369.

3. Stewart A, Webb J, Hewitt D. A survey of childhood malignancies. BMJ 1958;1:1495-1508.

4. Hujoel PP, Bollen AM, Noonan CJ, del Aguila MA. Antepartum dental radiography and infant low birth weight. JAMA 2004;291:1987-1993.

5. Brent RL. Commentary on JAMA article by Hujoel et al. Health Phys 2005;88:379-381.

6. Kahaleh M, Hartwell GD, Arseneau KO, et al. Safety and efficacy of ERCP in pregnancy. Gastrointest Endosc 2004;60:287-292.

7. Tham TC, Vandervoort J, Wong RC, et al. Safety of ERCP during pregnancy [see comment]. Am J Gastroenterol 2003;98:308-311.

8. ACOG Bulletins. ACOG Committee Opinion No. 299: Guidelines for diagnostic imaging during pregnancy. Obstet Gynecol 2004;104:647-651.

9. Roman E, Ansell G, Bull D. Leukaemia and non-Hodgkin’s lymphoma in children and young adults: are prenatal and neonatal factors important determinants of disease? Br J Cancer 1997;76:406-415.

10. Shu XO, Potter JD, Linet MS, et al. Diagnostic X-rays and ultrasound exposure and risk of childhood acute lymphoblastic leukemia by immunophenotype. Cancer Epidemiol Biomarkers Prev 2002;11:177-185.

11. McKinney PA, Cartwright RA, Saiu JM, et al. The inter-regional epidemiological study of childhood cancer (IRESCC): a case control study of aetiological factors in leukaemia and lymphoma. Arch Dis Child 1987;62:279-287.

12. Rodvall Y, Pershagen G, Hrubec Z, Ahlbom A, Pedersen NL, Boice JD. Prenatal X-ray exposure and childhood cancer in Swedish twins. Int J Cancer 1990;46:362-365.

13. Shu XO, Jin F, Linet MS, et al. Diagnostic X-ray and ultrasound exposure and risk of childhood cancer. Br J Cancer 1994;70:531-536.

14. Naumburg E, Bellocco R, Cnattingius S, Hall P, Boice JD, Ekbom A. Intrauterine exposure to diagnostic X rays and risk of childhood leukemia subtypes. Radiat Res 2001;156:718-723.

15. Schuz J, Kaletsch U, Kaatsch P, Meinert R, Michaelis J. Risk factors for pediatric tumors of the central nervous system: results from a German population-based case-control study. Med Pediatr Oncol 2001;36:274-282.

16. Shiono PH, Chung CS, Myrianthopoulos NC. Preconception radiation, intrauterine diagnostic radiation, and childhood neoplasia. J Natl Cancer Inst 1980;65:681-686.

17. Meinert R, Kaletsch U, Kaatsch P, Schuz J, Michaelis J. Associations between childhood cancer and ionizing radiation: results of a population-based case-control study in Germany. Cancer Epidemiol Biomarkers Prev 1999;8:793-799.

Article PDF
Author and Disclosure Information

Ariel K. Smits, MD, MPH
Heather L. Paladine, MD
Dolores Zegar Judkins, MLS
Oregon Health and Science University, Portland

Issue
The Journal of Family Practice - 55(5)
Publications
Topics
Page Number
441-443
Sections
Author and Disclosure Information

Ariel K. Smits, MD, MPH
Heather L. Paladine, MD
Dolores Zegar Judkins, MLS
Oregon Health and Science University, Portland

Author and Disclosure Information

Ariel K. Smits, MD, MPH
Heather L. Paladine, MD
Dolores Zegar Judkins, MLS
Oregon Health and Science University, Portland

Article PDF
Article PDF
EVIDENCE-BASED ANSWER

There is no evidence of significant risk to the developing fetus from any single diagnostic x-ray exposure (strength of recommendation: C, based on non-homogenous case-control studies). No studies were found on fetal exposure risks from other forms of diagnostic radiation such as computed tomography (CT) scans, fluoroscopy, or mammography. Prudent clinicians should order only those studies that result in clinically important information and efforts should be made to minimize fetal exposure.

CLINICAL COMMENTARY

Communication with the patient can go a long way to alleviate concerns regarding effects of radiation
Timothy Huber, MD
Oroville, Calif

The lack of high-quality research coupled with a general societal fear of radiation during pregnancy can create tension between the physician and the patient who needs diagnostic studies during pregnancy. This review reassures the conscientious practitioner that there is little to fear from the prudent use of routine studies. There is less clarity when a woman needs multiple or higher-dose radiation studies, especially in the first trimester.

Patients need our best estimates regarding the medical necessity, diagnostic benefit, and overall risk in these situations. Open communication with the patient can go a long way to alleviate concerns regarding the possible teratogenic or carcinogenic effects of radiation. Working more closely with our radiology colleagues to determine the best set of studies for a particular situation can help reduce the overall total radiation exposure. I refer patients who are Internet-savvy to www.familydoctor.org for more information about diagnostic radiation exposure in pregnancy.

 

Evidence summary

Clinicians have been concerned about x-ray exposure during pregnancy since the 1950s. Much of this concern was based on the Oxford Survey of Childhood Leukemia, as well as other early case-control studies.1-3 These studies reported an approximate 40% increase in the risk of childhood leukemia among offspring of women who received diagnostic x-rays in pregnancy. However, by modern standards, these studies are of poor quality as they are limited by reliance on maternal recall of prenatal x-ray exposure, lack of consideration for multiple confounding factors, lack of blinding in determination of exposure and outcome status, limitations in selection of both cases and controls, and other significant methodological flaws.

Modern, well-designed studies have failed to replicate the association between in utero radiation and childhood malignancies found in the early studies. We found 1 good-quality and 5 fair-quality case-control studies examining the association between in utero x-ray exposure and childhood leukemia, as well as 6 fair-quality case-control studies examining the association with other childhood malignancies. These studies found no significant association between in utero exposure to any x-ray in general, or to abdominal or pelvic x-rays and development of subsequent childhood leukemia, central nervous system tumors or other malignancies (TABLE).

No meta-analyses, randomized controlled trials, cohort studies or good- or fair-quality case-control studies were found examining in utero x-rays and decreased head circumference, congenital malformations, spontaneous abortion, low birth weight, or developmental problems. One recent, fair-quality case-control study found an association between prenatal dental x-rays and low birth weight (odds ratio [OR]=1.8 [95% confidence interval, 1.09–1.36]) for radiation exposures above 0.4 Gy.4 However, this study has been criticized for several reasons, including lack of biological plausibility and failure to control for dental disease.5

There does not appear to be an increased risk of adverse pregnancy outcomes with prenatal endoscopic retrograde cholangiopancreaticogram (ERCP), though this conclusion is based on 2 incomplete case series reports with no follow-up of the infants after delivery.6,7 No good- or fair-quality studies were found examining the association between other diagnostic radiation exposures (CT scan, mammography, positron emission tomography scan, dual-energy x-ray absorptiometry [DEXA]) with adverse pregnancy outcomes.

TABLE
Risk of childhood malignancy after in utero diagnostic X-ray studies1

OUTCOMETYPE OF STUDYODDS RATIO [95% CI]
Leukemia9-14Any x-ray0.8–1.8 [0.5–3.6]
Pelvic x-ray0.7–3.4 [0.4–12.9]
CNS tumor12,15Any x-ray0.78 [0.44–1.36]
Abdominal x-ray1.5 [0.5–4.2]
Any cancer12,13,16,17Any x-ray0.92–1.2 [0.47–2.4]
Abdominal x-ray1.4 [0.8–2.5]

Recommendations from others

The American College of Obstetricians and Gynecologists recommends that women be counseled that x-ray exposure from a single diagnostic procedure does not result in harmful fetal effects. Concern about possible effects of ionizing radiation exposure should not prevent medically indicated diagnostic x-ray procedures from being performed on a pregnant woman.8

EVIDENCE-BASED ANSWER

There is no evidence of significant risk to the developing fetus from any single diagnostic x-ray exposure (strength of recommendation: C, based on non-homogenous case-control studies). No studies were found on fetal exposure risks from other forms of diagnostic radiation such as computed tomography (CT) scans, fluoroscopy, or mammography. Prudent clinicians should order only those studies that result in clinically important information and efforts should be made to minimize fetal exposure.

CLINICAL COMMENTARY

Communication with the patient can go a long way to alleviate concerns regarding effects of radiation
Timothy Huber, MD
Oroville, Calif

The lack of high-quality research coupled with a general societal fear of radiation during pregnancy can create tension between the physician and the patient who needs diagnostic studies during pregnancy. This review reassures the conscientious practitioner that there is little to fear from the prudent use of routine studies. There is less clarity when a woman needs multiple or higher-dose radiation studies, especially in the first trimester.

Patients need our best estimates regarding the medical necessity, diagnostic benefit, and overall risk in these situations. Open communication with the patient can go a long way to alleviate concerns regarding the possible teratogenic or carcinogenic effects of radiation. Working more closely with our radiology colleagues to determine the best set of studies for a particular situation can help reduce the overall total radiation exposure. I refer patients who are Internet-savvy to www.familydoctor.org for more information about diagnostic radiation exposure in pregnancy.

 

Evidence summary

Clinicians have been concerned about x-ray exposure during pregnancy since the 1950s. Much of this concern was based on the Oxford Survey of Childhood Leukemia, as well as other early case-control studies.1-3 These studies reported an approximate 40% increase in the risk of childhood leukemia among offspring of women who received diagnostic x-rays in pregnancy. However, by modern standards, these studies are of poor quality as they are limited by reliance on maternal recall of prenatal x-ray exposure, lack of consideration for multiple confounding factors, lack of blinding in determination of exposure and outcome status, limitations in selection of both cases and controls, and other significant methodological flaws.

Modern, well-designed studies have failed to replicate the association between in utero radiation and childhood malignancies found in the early studies. We found 1 good-quality and 5 fair-quality case-control studies examining the association between in utero x-ray exposure and childhood leukemia, as well as 6 fair-quality case-control studies examining the association with other childhood malignancies. These studies found no significant association between in utero exposure to any x-ray in general, or to abdominal or pelvic x-rays and development of subsequent childhood leukemia, central nervous system tumors or other malignancies (TABLE).

No meta-analyses, randomized controlled trials, cohort studies or good- or fair-quality case-control studies were found examining in utero x-rays and decreased head circumference, congenital malformations, spontaneous abortion, low birth weight, or developmental problems. One recent, fair-quality case-control study found an association between prenatal dental x-rays and low birth weight (odds ratio [OR]=1.8 [95% confidence interval, 1.09–1.36]) for radiation exposures above 0.4 Gy.4 However, this study has been criticized for several reasons, including lack of biological plausibility and failure to control for dental disease.5

There does not appear to be an increased risk of adverse pregnancy outcomes with prenatal endoscopic retrograde cholangiopancreaticogram (ERCP), though this conclusion is based on 2 incomplete case series reports with no follow-up of the infants after delivery.6,7 No good- or fair-quality studies were found examining the association between other diagnostic radiation exposures (CT scan, mammography, positron emission tomography scan, dual-energy x-ray absorptiometry [DEXA]) with adverse pregnancy outcomes.

TABLE
Risk of childhood malignancy after in utero diagnostic X-ray studies1

OUTCOMETYPE OF STUDYODDS RATIO [95% CI]
Leukemia9-14Any x-ray0.8–1.8 [0.5–3.6]
Pelvic x-ray0.7–3.4 [0.4–12.9]
CNS tumor12,15Any x-ray0.78 [0.44–1.36]
Abdominal x-ray1.5 [0.5–4.2]
Any cancer12,13,16,17Any x-ray0.92–1.2 [0.47–2.4]
Abdominal x-ray1.4 [0.8–2.5]

Recommendations from others

The American College of Obstetricians and Gynecologists recommends that women be counseled that x-ray exposure from a single diagnostic procedure does not result in harmful fetal effects. Concern about possible effects of ionizing radiation exposure should not prevent medically indicated diagnostic x-ray procedures from being performed on a pregnant woman.8

References

1. Fattibene P, Mazzei F, Nuccetelli C, Risica S. Prenatal exposure to ionizing radiation: sources, effects and regulatory aspects. Acta Paediatr 1999;88:693-702.

2. Bross ID, Natarajan N. Risk of leukemia in susceptible children exposed to preconception, in utero and postnatal radiation. Prev Med 1974;3:361-369.

3. Stewart A, Webb J, Hewitt D. A survey of childhood malignancies. BMJ 1958;1:1495-1508.

4. Hujoel PP, Bollen AM, Noonan CJ, del Aguila MA. Antepartum dental radiography and infant low birth weight. JAMA 2004;291:1987-1993.

5. Brent RL. Commentary on JAMA article by Hujoel et al. Health Phys 2005;88:379-381.

6. Kahaleh M, Hartwell GD, Arseneau KO, et al. Safety and efficacy of ERCP in pregnancy. Gastrointest Endosc 2004;60:287-292.

7. Tham TC, Vandervoort J, Wong RC, et al. Safety of ERCP during pregnancy [see comment]. Am J Gastroenterol 2003;98:308-311.

8. ACOG Bulletins. ACOG Committee Opinion No. 299: Guidelines for diagnostic imaging during pregnancy. Obstet Gynecol 2004;104:647-651.

9. Roman E, Ansell G, Bull D. Leukaemia and non-Hodgkin’s lymphoma in children and young adults: are prenatal and neonatal factors important determinants of disease? Br J Cancer 1997;76:406-415.

10. Shu XO, Potter JD, Linet MS, et al. Diagnostic X-rays and ultrasound exposure and risk of childhood acute lymphoblastic leukemia by immunophenotype. Cancer Epidemiol Biomarkers Prev 2002;11:177-185.

11. McKinney PA, Cartwright RA, Saiu JM, et al. The inter-regional epidemiological study of childhood cancer (IRESCC): a case control study of aetiological factors in leukaemia and lymphoma. Arch Dis Child 1987;62:279-287.

12. Rodvall Y, Pershagen G, Hrubec Z, Ahlbom A, Pedersen NL, Boice JD. Prenatal X-ray exposure and childhood cancer in Swedish twins. Int J Cancer 1990;46:362-365.

13. Shu XO, Jin F, Linet MS, et al. Diagnostic X-ray and ultrasound exposure and risk of childhood cancer. Br J Cancer 1994;70:531-536.

14. Naumburg E, Bellocco R, Cnattingius S, Hall P, Boice JD, Ekbom A. Intrauterine exposure to diagnostic X rays and risk of childhood leukemia subtypes. Radiat Res 2001;156:718-723.

15. Schuz J, Kaletsch U, Kaatsch P, Meinert R, Michaelis J. Risk factors for pediatric tumors of the central nervous system: results from a German population-based case-control study. Med Pediatr Oncol 2001;36:274-282.

16. Shiono PH, Chung CS, Myrianthopoulos NC. Preconception radiation, intrauterine diagnostic radiation, and childhood neoplasia. J Natl Cancer Inst 1980;65:681-686.

17. Meinert R, Kaletsch U, Kaatsch P, Schuz J, Michaelis J. Associations between childhood cancer and ionizing radiation: results of a population-based case-control study in Germany. Cancer Epidemiol Biomarkers Prev 1999;8:793-799.

References

1. Fattibene P, Mazzei F, Nuccetelli C, Risica S. Prenatal exposure to ionizing radiation: sources, effects and regulatory aspects. Acta Paediatr 1999;88:693-702.

2. Bross ID, Natarajan N. Risk of leukemia in susceptible children exposed to preconception, in utero and postnatal radiation. Prev Med 1974;3:361-369.

3. Stewart A, Webb J, Hewitt D. A survey of childhood malignancies. BMJ 1958;1:1495-1508.

4. Hujoel PP, Bollen AM, Noonan CJ, del Aguila MA. Antepartum dental radiography and infant low birth weight. JAMA 2004;291:1987-1993.

5. Brent RL. Commentary on JAMA article by Hujoel et al. Health Phys 2005;88:379-381.

6. Kahaleh M, Hartwell GD, Arseneau KO, et al. Safety and efficacy of ERCP in pregnancy. Gastrointest Endosc 2004;60:287-292.

7. Tham TC, Vandervoort J, Wong RC, et al. Safety of ERCP during pregnancy [see comment]. Am J Gastroenterol 2003;98:308-311.

8. ACOG Bulletins. ACOG Committee Opinion No. 299: Guidelines for diagnostic imaging during pregnancy. Obstet Gynecol 2004;104:647-651.

9. Roman E, Ansell G, Bull D. Leukaemia and non-Hodgkin’s lymphoma in children and young adults: are prenatal and neonatal factors important determinants of disease? Br J Cancer 1997;76:406-415.

10. Shu XO, Potter JD, Linet MS, et al. Diagnostic X-rays and ultrasound exposure and risk of childhood acute lymphoblastic leukemia by immunophenotype. Cancer Epidemiol Biomarkers Prev 2002;11:177-185.

11. McKinney PA, Cartwright RA, Saiu JM, et al. The inter-regional epidemiological study of childhood cancer (IRESCC): a case control study of aetiological factors in leukaemia and lymphoma. Arch Dis Child 1987;62:279-287.

12. Rodvall Y, Pershagen G, Hrubec Z, Ahlbom A, Pedersen NL, Boice JD. Prenatal X-ray exposure and childhood cancer in Swedish twins. Int J Cancer 1990;46:362-365.

13. Shu XO, Jin F, Linet MS, et al. Diagnostic X-ray and ultrasound exposure and risk of childhood cancer. Br J Cancer 1994;70:531-536.

14. Naumburg E, Bellocco R, Cnattingius S, Hall P, Boice JD, Ekbom A. Intrauterine exposure to diagnostic X rays and risk of childhood leukemia subtypes. Radiat Res 2001;156:718-723.

15. Schuz J, Kaletsch U, Kaatsch P, Meinert R, Michaelis J. Risk factors for pediatric tumors of the central nervous system: results from a German population-based case-control study. Med Pediatr Oncol 2001;36:274-282.

16. Shiono PH, Chung CS, Myrianthopoulos NC. Preconception radiation, intrauterine diagnostic radiation, and childhood neoplasia. J Natl Cancer Inst 1980;65:681-686.

17. Meinert R, Kaletsch U, Kaatsch P, Schuz J, Michaelis J. Associations between childhood cancer and ionizing radiation: results of a population-based case-control study in Germany. Cancer Epidemiol Biomarkers Prev 1999;8:793-799.

Issue
The Journal of Family Practice - 55(5)
Issue
The Journal of Family Practice - 55(5)
Page Number
441-443
Page Number
441-443
Publications
Publications
Topics
Article Type
Display Headline
What are the risks to the fetus associated with diagnostic radiation exposure during pregnancy?
Display Headline
What are the risks to the fetus associated with diagnostic radiation exposure during pregnancy?
Sections
PURLs Copyright

Evidence-based answers from the Family Physicians Inquiries Network

Disallow All Ads
Alternative CME
Article PDF Media