Do I need to tell the MRI center that I am pregnant?

Yes, and tell them if you might be pregnant. The ACR asks facilities to screen for unsuspected pregnancy before giving gadolinium contrast. Your answer changes whether contrast is used and how the radiologist plans the scan.

Is a 3 tesla MRI okay during pregnancy?

The ACR-SPR fetal MRI practice parameter cites published work on the safety of maternal and fetal MRI at 3 tesla, and most clinical fetal imaging runs at 1.5 or 3 tesla. Scanners above 3 tesla are research tools with less pregnancy data. Ask the radiologist which field strength they plan to use.

Will the MRI noise hurt the baby?

ACOG reviewed the available human studies and found no documented acoustic injuries to fetuses during prenatal MRI. The mother's abdomen and amniotic fluid dampen the sound. You will still get earplugs or headphones for your own hearing.

What if I had an MRI before I knew I was pregnant?

A non-contrast MRI in early pregnancy has not been linked to harm. The Ontario cohort of 1,737 first-trimester MRI exposures found no significant increase in stillbirth, congenital anomalies, or vision or hearing loss. If contrast was given, tell your obstetrician so it is in your record.

Can MRI be used to look at the baby directly?

Yes. Fetal MRI is an established exam that adds detail when ultrasound cannot answer a question, most often for the fetal brain, spine, and chest. It is done without contrast. Ultrasound remains the first-line test for pregnancy imaging.

Can You Get An MRI While Pregnant?

The short answer: Yes. The American College of Obstetricians and Gynecologists (ACOG) lists MRI, with ultrasound, as an imaging technique of choice for pregnant patients, and it says MRI is not associated with fetal risk. There is no trimester in which a needed MRI is off limits. The one real caution is gadolinium contrast, which crosses the placenta and is used in pregnancy only when it will change care.

Is an MRI safe during pregnancy?

MRI uses a strong magnet and radio waves. It does not use ionizing radiation, the kind found in X-rays and CT scans. The FDA states that MR images are made without any ionizing radiation, so patients are not exposed to its harmful effects. MedlinePlus adds that no side effects from the magnetic fields and radio waves have been reported.

The obstetric guidance is clear. ACOG Committee Opinion 723, endorsed by the American College of Radiology, says ultrasound and MRI are not associated with risk and are the imaging techniques of choice for the pregnant patient. The same document says there are no precautions or contraindications specific to the pregnant woman.

ACOG names three theoretical concerns: birth defects, tissue heating, and hearing damage to the fetus. It reports no evidence of actual harm from any of them. No published human studies document birth defects, heating is negligible near the uterus, and human studies have found no acoustic injuries to fetuses.

The guidance comes with a condition. MRI should be used prudently and only when it is expected to answer a relevant clinical question or provide medical benefit. A doctor should not order an MRI in pregnancy for curiosity, and should not withhold one that is needed.

Does the first trimester change the answer?

Not according to the two societies that set imaging policy. ACOG reports that the American College of Radiology, after reviewing the data on birth defects, concludes that no special consideration is recommended for the first trimester versus any other. The ACR-SPR practice parameter for fetal MRI, revised in 2025, cites studies showing normal pediatric assessments at 9 months in infants exposed to MRI in utero.

You will still see more cautious language on some educational pages. The National Institute of Biomedical Imaging and Bioengineering notes that no effects on the fetus have been demonstrated, but suggests avoiding MRI as a precaution, especially in the first trimester. Read that as a default for scans that can wait, not a ban.

In practice, non-urgent scans are often scheduled after delivery. Urgent scans, for a suspected stroke, appendicitis, or a spinal problem, proceed in any trimester.

Why is gadolinium contrast the real question?

The magnet is not the issue. The contrast dye is. Gadolinium-based agents are injected to make certain tissues, tumors, and blood vessels stand out. Our guide to MRI with contrast explains when radiologists add it.

ACOG explains the concern. Gadolinium is water soluble and crosses the placenta into the fetal circulation and the amniotic fluid. The fetus swallows amniotic fluid, so the contrast re-enters the fetal circulation and the total duration of exposure is unknown. Free gadolinium is toxic, and the longer it stays in amniotic fluid, the greater the chance it separates from the molecule that binds it. In animals, gadolinium agents were teratogenic at high and repeated doses.

FDA-approved labeling says the same thing in regulatory language. The Gadavist (gadobutrol) label states that gadolinium-based agents cross the placenta and result in fetal exposure. Contrast was seen in the placenta and fetal tissues after maternal dosing. In pregnant monkeys, gadolinium was measurable in offspring bone, brain, skin, liver, kidney, and spleen for at least 7 months. The label also lists pregnant patients among groups who might be at higher risk from gadolinium retention.

So the rules are strict. ACOG says gadolinium may be used in a pregnant woman only if it significantly improves diagnostic performance and is expected to improve fetal or maternal outcome. The ACR position statement from August 2022 says to avoid routine administration of gadolinium to pregnant patients, and asks every facility to screen for unsuspected pregnancy before giving it. ACOG notes that non-contrast MRI answers most questions in pregnancy, including placental implantation problems, without contrast.

What did the large Ontario study find?

Most of what we know about real outcomes comes from one cohort. Ray and colleagues published it in JAMA in 2016. They reviewed 1,424,105 deliveries in Ontario, Canada, between 2003 and 2015. Of those, 1,737 pregnancies had a first-trimester MRI and 397 had a gadolinium MRI at some point in pregnancy.

First-trimester MRI without contrast came out clean. Compared with no MRI, the adjusted relative risk for stillbirth or neonatal death was 1.68, with a 95% confidence interval of 0.97 to 2.90. That interval crosses 1, so the difference was not statistically significant. The adjusted hazard ratio for congenital anomalies was 1.16 (95% CI, 0.96 to 1.40), also not significant. The authors concluded that first-trimester MRI was not associated with increased risk of harm to the fetus or in early childhood.

Gadolinium MRI looked different. Stillbirth or neonatal death occurred in 7 of the 397 gadolinium-exposed pregnancies, an adjusted relative risk of 3.70 (95% CI, 1.55 to 8.85). Any rheumatologic, inflammatory, or infiltrative skin condition in the child occurred more often as well, with an adjusted hazard ratio of 1.36 (95% CI, 1.09 to 1.69).

ACOG points out two limits. The comparison group had no MRI at all, rather than an MRI without contrast, so sicker patients who needed contrast may explain part of the gap. And the skin and inflammatory outcomes are rare and hard to detect. Even so, ACOG cites these results, plus the animal data, as the reason gadolinium should be limited to cases where benefits clearly outweigh possible risks.

How does MRI compare with CT and X-ray in pregnancy?

MRI wins on radiation because it has none. ACOG notes that, with few exceptions, radiation from X-ray, CT, or nuclear medicine is far below the dose linked to fetal harm, and those tests should not be withheld when needed. Still, when MRI and CT can both answer the question, MRI is preferred in pregnancy.

Appendicitis is the textbook example. ACOG says MRI is similar to ultrasound for diagnosing appendicitis but is preferred when readily available, because ultrasound more often fails to see the appendix. For a broader comparison of the two modalities, see MRI vs CT scan.

What happens at the appointment when you are pregnant?

The scan itself is the same. The FDA notes that radiofrequency energy can heat the body, and that the potential rises in long exams. Pregnancy protocols favor shorter sequences.

Three things differ. The screening form asks about pregnancy, so answer it honestly, including if you might be pregnant. If contrast was ordered, expect the radiologist to reconsider it or switch to a non-contrast protocol. Later in pregnancy, lying flat can be uncomfortable, and some centers position you on your side or with a wedge. If this is your first scan, what to expect at your first MRI walks through the rest. If you are unsure whether a symptom needs imaging at all, symptom.md covers how to sort urgent symptoms from ones that can wait.

Can you breastfeed after a gadolinium scan?

Yes, without a pause. ACOG states that breastfeeding should not be interrupted after gadolinium administration. Less than 0.04% of an intravenous dose is excreted into breast milk within the first 24 hours. Of that tiny amount, the infant absorbs less than 1% through the gut. No reports of harm exist.

Some imaging centers still hand out a "pump and dump" instruction for 24 hours. ACOG's position is that this is unnecessary.

The bottom line

A non-contrast MRI is safe to have during pregnancy, in any trimester, when a doctor needs the answer it gives. ACOG and the ACR both say so, and the largest cohort to date found no significant fetal harm from first-trimester MRI. Gadolinium contrast is the exception: it crosses the placenta, and the same cohort linked it to worse outcomes. Radiologists give it in pregnancy only when it will change treatment. Breastfeeding after gadolinium does not need to stop.

Last updated: September 2026. This article is for informational purposes only and does not constitute medical advice. Talk to your obstetrician and the radiology team about whether an MRI, with or without contrast, is right for your pregnancy.