In utero x-ray exposure and subsequent cancer risk

January 01, 0001

In utero x-ray exposure and subsequent cancer risk

These US researchers examined whether exposure to X-rays or ultrasound in utero and during the first 100 days post-partum was associated with an increased risk of cancer. They performed a case-control study using the United Kingdom Childhood Cancer Study (UKCCS), garnering childhood cancer cases (n=2990) and matched controls (n=4858)

The researchers found: "Logistic regression models conditioned on matching factors, with adjustment for maternal age and child’s birth weight, showed no evidence of increased risk of childhood cancer with in utero exposure to ultrasound scans. Some indication existed of a slight increase in risk after in utero exposure to x rays for all cancers (odds ratio 1.l4) and leukaemia (1.36), but this was not statistically significant. Exposure to diagnostic x rays in early infancy (0-100 days) was associated with small, non- significant excess risks for all cancers and leukaemia, as well as increased risk of lymphoma (odds ratio 5.14) on the basis of small numbers."

The researchers concluded: "Although the results for lymphoma need to be replicated, all of the findings indicate possible risks of cancer from radiation at doses lower than those associated with commonly used procedures such as computed tomography scans, suggesting the need for cautious use of diagnostic radiation imaging procedures to the abdomen/pelvis of the mother during pregnancy and in children at very young ages."

Although not definitive evidence, these data raise concern of cancer risk for in utero exposure to X-rays

For the full abstract, click here.

BMJ 3421:d472, 10 February 2011
© 2011 BMJ Publishing Group Ltd.
Early life exposure to diagnostic radiation and ultrasound scans and risk of childhood cancer: case-control study. Preetha Rajaraman, Jill Simpson, Gila Neta, et al. Correspondence to P Rajaraman: [email protected]

Category: W. Pregnancy, Family Planning. Keywords: x-ray, ultrasound, cancer, leukemia, lymphoma, case-control study, journal watch.
Synopsis edited by Dr Paul Schaefer, Toledo, Ohio. Posted on Global Family Doctor 4 March 2011

Pearls are an independent product of the Cochrane primary care group and are meant for educational use and not to guide clinical care.