X-Rays During Pregnancy: What to Know

Medically Reviewed by Dany Paul Baby, MD on April 20, 2022
Written by Parang Mehta
4 min read

X-rays during pregnancy have long been considered unsafe. The radiation could potentially harm your baby, even causing birth defects. 

Sometimes, however, getting an x-ray while you are pregnant may be necessary. If you've hurt your leg in a car crash, for example, your physician may need it. 

Does an x-ray affect pregnancy? Are the effects of radiation exposure during pregnancy truly dangerous? Is there any way to mitigate the potential risks?

X-rays are electromagnetic waves with wavelengths falling between ultraviolet light and gamma rays. They're classified as ionizing radiation. 

Much of our knowledge of the dangers of radiation in pregnancy has come from the nuclear explosions in World War II. However, x-rays used in medicine do not produce that level of radiation exposure to mother or baby.

Because of the effects seen after the massive radiation exposure, x-rays have been feared during pregnancy, but now, scientists have found that a single x-ray of your limbs or teeth can be quite safe for your baby.

The developing baby is largely protected from the radiation by the abdominal wall and the uterus, but some radiation does get through. Developing babies are very sensitive to it. 

Moreover, the radiation of multiple x-rays adds up in its effects. If radiation exposure is significant, the results can be:

  • Growth restriction
  • Birth malformations
  • Disturbed brain function
  • Cancer

Though these dangers are known, they are also rare. For example, the projected risk of later cancer is 2% greater in later life, but that projection follows a radiation dose equal to about 500 x-rays of the chest.

The risk for brain effects is greatest at weeks 10 to 17 of pregnancy. Procedures using high doses of radiation should, consequently, be avoided during this period.

Extremely high doses of radiation will have severe effects on fetuses, though. Microcephaly (small head with brain malformation), microphthalmia (small eyes), genital and skeletal malformations, cataracts, and low birth weights can result from such massive radiation exposure. 

These doses are far higher than those used by doctors, though.

Yes, you can, as long as it isn't of your belly, which would expose your baby. Your baby is especially at risk in the first few weeks of pregnancy. 

X-rays of your limbs, teeth, head, and chest tend to be safe enough, though. They do not expose your baby to direct radiation. 

X-rays of the belly, pelvis, kidneys, or lower back, on the other hand, do expose your baby to radiation and should be avoided. 

High-dose x-rays administered early in pregnancy can affect your baby. In the first two weeks of pregnancy, a miscarriage may result from such exposure. 

At this time, the embryo is only a few cells, and damage or death of even one or two cells will cause the death of the embryo.

Babies exposed between the second and eighth week, meanwhile, are likely to experience reduced growth, as well as birth defects. 

Babies exposed between 8 and 16 are at a higher risk for intellectual and learning disabilities.

However, higher doses of x-rays are used during a computed tomography (CT) scan or a nuclear medicine scan. A nuclear medicine scan involves injecting a radioactive substance that the camera is able to see. The radiation dose is much higher than a single x-ray. 

A CT scan of the pelvis or belly during the early weeks of pregnancy is also a hazard. The baby has an increased risk of childhood cancer following such procedures.

A barium enema involves pushing a liquid containing barium into your rectum and then taking a series of x-ray pictures. During this procedure, the radiation exposure to your baby is much higher than a single x-ray, so this test should be avoided when you're pregnant.

Always let your physician know if you are, or might be, pregnant. They will decide on the appropriate precautions.

If your medical issue is not urgent, they may postpone taking x-rays until after the birth of your baby.

If the pregnancy x-ray is of the limbs, head, or neck, they will give you a lead apron. This apron covers your belly and doesn't allow the x-rays to reach your baby. 

Alternatively, your doctor may decide to use another imaging method. Ultrasound and magnetic resonance imaging (MRI) do not use ionizing radiation. They are considered safe to use during pregnancy.

What if you had an x-ray of the belly before discovering that you were pregnant? 

You should inform your doctor. The radiation from a single x-ray is tiny, though, so your doctor is unlikely to be overly concerned. 

What about a high-dose radiation x-ray procedure? 

Barium enemas and CT scans use higher doses of radiation than single x-rays. Some cardiac procedures and orthopedic operations are also done under x-ray guidance. They use doses of radiation that should be avoided in pregnancy.

If you have had such exposure before learning you were pregnant, talk to your doctor. 

To avoid such occurrences, some hospitals test all women above the age of 12 years for pregnancy before undergoing any such procedure.

It's not desirable to be x-rayed while you are pregnant, but there's no need to be terrified. Modern x-ray units use low doses of radiation. The amount of radiation for a single x-ray, in fact, is not likely to harm your baby at all. If your physician decides you need an x-ray, the risk of not getting one is probably greater than that posed by the radiation.

The timing of the x-ray is also important. Before 18 weeks of pregnancy, babies are very sensitive to radiation. They're likely to be harmed by it. Beyond 26 weeks of pregnancy, though, your baby has the same sensitivity to radiation as a newborn baby.

Your physician will probably avoid taking an x-ray while you're pregnant, but sometimes, an x-ray is needed to diagnose and treat an illness. Such treatment is sometimes necessary to keep you and your baby healthy.