If you are pregnant or suspect you are pregnant, you should inform the MRI technologist and/or radiologist during the screening procedure that is conducted before the MRI examination. Otherwise, you should be asked about this matter anyway. In general, there is no known risk of using MRI during pregnancy. However, MRI is reserved for use in pregnant patients only to address very important problems or suspected abnormalities – but MRI is safer for the fetus than imaging with X-rays or CT.
Therefore, we do not recommend patients to have an MRI during their pregnancy unless it is medically indicated. These cases should be handled on an individual basis. While there is no known risk to MRI, it is considered prudent to wait until after the pregnancy if possible, because conclusive information showing how safe MRI is for pregnant women and the fetus is not yet available. MR imaging is generally not performed on women in the first twelve weeks of pregnancy (first trimester) at all. Depending on the condition, there may be other exams available, such as ultrasound, to help diagnose a medical condition.
If there is a severe medical reason for an MRI, your physician may consult with a radiologist to determine if MRI is the best course of action before proceeding. As an option, an abbreviated MRI exam may be performed, to reduce the time in the magnetic field, based on the recommendation of the referring physician and radiologist.
You should inform your radiologist if you are breastfeeding at the time of a scheduled MRI study. Especially in case, when you may need to receive an MRI contrast agent. MRI contrast agents are usually excreted with your urine, however, until it reaches your kidneys, contrast may get through the blood flow to your breasts and pass to the breast milk. Although the amount of contrast agent which can your baby get is minimal, it is recommended to avoid breastfeeding. One possible solution under this circumstance is to pump breast milk before the study, to be used until injected contrast material has cleared from the body, which typically takes about 24 hours. The radiologist will provide additional information to you regarding this matter.