Pregnancy Scans: Safe Options For Expectant Mothers (2024)

Ultrasound and magnetic resonance imaging (MRI) are considered safe for pregnant women and are the imaging techniques of choice for medical professionals. Ultrasound has been used to monitor pregnancy for decades and there is no evidence that it can cause harm to a developing fetus. However, there is a growing trend of pregnant women undergoing computed tomography (CT) scans, which expose mothers and fetuses to radiation. While the amount of radiation used in CT scans is still considered safe, alternative methods that do not use radiation should be considered to avoid unnecessary exposure.

Ultrasound scans are safe and commonly used during pregnancy

Ultrasound scans use sound waves to capture images of the foetus inside the uterus and are helpful in estimating how far along a pregnancy is. While some women may choose to skip the initial scan, healthcare providers recommend all women have an anatomy scan, usually performed around the 20th week of gestation, to check for any developmental problems in the foetus. Ultrasound scans are also used to determine if a woman is carrying twins, or if her placenta is too low or her baby is breech as she goes into labour.

Ultrasound technology has been used to monitor pregnancies for decades and there is no evidence of any harm to the developing foetus. The American College of Obstetricians and Gynecologists (ACOG) notes that "no links have been found between ultrasound and birth defects, childhood cancer, or developmental problems later in life". While experts cannot rule out the possibility that future research may uncover certain effects, they recommend that pregnant women only undergo ultrasounds when necessary and that these are performed by trained providers as part of their prenatal care.

While some women may opt to refuse ultrasounds during pregnancy, healthcare providers emphasise the benefits of ultrasound as a screening and diagnostic tool. Ultrasound scans can detect serious developmental problems, some of which can be addressed in utero, and help determine if a woman needs to give birth at a specific type of facility with specialists on hand to care for the baby after birth.

MRI scans are safe during pregnancy

Pregnancy is a time of great excitement and anticipation, but also uncertainty. It is natural for parents-to-be to be conscious of their health and that of their unborn baby, and sometimes decisions need to be made to support the care of the pregnant person, the baby, or both.

Magnetic resonance imaging (MRI) is a non-invasive diagnostic imaging technique used to view internal organs and tissues in detail. It uses a combination of a strong magnetic field, radio waves, and a computer to generate images without the use of X-rays or ionising radiation.

There is no evidence that suggests MRI in pregnancy poses any risks to the mother or baby. However, it is important to seek advice from a doctor or clinician to get risk estimates and guidance about MRI safety, based on the type of scan, what it is needed for, and how far along the pregnancy is.

MRI scans do not use ionising radiation, so there is no risk of exposing the developing baby to X-ray radiation and the potential risk of damage to the baby's cells. Ultrasound is the most commonly used imaging exam during pregnancy, but if an ultrasound does not provide a clear answer, or if other parts of the body need to be imaged, an MRI may be needed to obtain the information a doctor requires.

While there is no evidence of harm, it is still important to be cautious. In some cases, it might be recommended to wait until after childbirth before having an MRI scan.

Some MRI scans require gadolinium contrast material to enhance the images, and the use of gadolinium is generally discouraged during pregnancy. There is a potentially slightly higher risk of a range of rheumatological and inflammatory conditions in early pregnancy where a gadolinium agent has been used.

The use of strong magnetic fields and radio frequencies is another concern, as there is a possibility that the heating effect of the scanner's technology could pose a risk to the unborn baby, especially during the first trimester. However, there is no evidence to prove this, and studies have shown no risk of birth defects or adverse outcomes linked to MRI in pregnancy.

High levels of noise in the MRI scan room could also pose a risk to the hearing of the unborn baby. However, based on some small studies, damage to foetal hearing has not been reported, and findings suggest no known risk of hearing loss.

MRI safety considerations also apply to pregnant health care practitioners, who can enter the MRI scan room for positioning patients but should not remain near the scanner during the scan itself.

X-rays are not recommended during pregnancy

While X-rays are not recommended during pregnancy, there are some instances where the benefits of an X-ray outweigh the potential risks.

X-rays are a form of ionizing radiation, which can be harmful when delivered in high quantities. While such high quantities are seldom reached in medical imaging exams, there is still a potential risk to the foetus. The unborn child is very sensitive to the effects of radiation, and exposure to high doses can cause miscarriages, birth defects, and some cancers later in life. Therefore, it is important for your doctor to be aware of your pregnancy when an X-ray, CT scan or nuclear imaging examination is being considered.

If you are pregnant and require an X-ray, your doctor may decide to cancel, postpone, or modify the procedure to reduce the amount of radiation. Alternatively, your doctor may determine that the benefits of the X-ray outweigh the risks and proceed as planned. In any case, you should feel free to discuss the decision with your doctor.

To minimise the risks, it is important to inform your doctor if you are pregnant or think you might be, even in the early weeks of pregnancy. Additionally, if you are pregnant, it is recommended to avoid being in the same room while someone else is having an X-ray done. If you need to hold a child who is being X-rayed, be sure to wear a lead apron to protect your reproductive organs and your baby.

While X-rays are not recommended during pregnancy, other imaging techniques such as ultrasound and magnetic resonance imaging (MRI) are considered safe and are the preferred methods for pregnant patients. These techniques use non-ionizing radiation and are not associated with risk to the foetus.

CT scans are controversial during pregnancy

While medical imaging exams are generally safe during pregnancy, CT scans are a source of controversy due to the use of ionizing radiation. This type of radiation can be harmful when delivered in high quantities, but such quantities are seldom reached in medical imaging exams.

The potential risk of harm from CT scans is very small, but it is important for doctors to be aware of a patient's pregnancy to select the most appropriate imaging exam and keep radiation exposure as low as possible. The amount of radiation used in normal CT imaging has never been shown to cause harm to an unborn child. However, there may be a very slight risk to the baby if the CT scan examines the abdomen or pelvis area. In such cases, an unborn baby may have about a one in 1,000 greater chance of developing cancer as a child. It is important to note that the level of risk is not proven and may be nonexistent.

The use of CT scans during pregnancy is a decision that should be made jointly by the doctor and the patient, taking into account the potential benefits and risks. While CT scans can provide valuable diagnostic information, alternative imaging techniques such as ultrasound or magnetic resonance imaging (MRI) that do not involve ionizing radiation may be preferred whenever possible during pregnancy.

section title: Ionizing radiation and pregnancy

Ionizing Radiation and Pregnancy

Ionizing radiation carries potential health risks to the developing fetus, including congenital abnormalities, developmental delays, or cancer. It is important to minimize radiation exposure during pregnancy.

Ionizing radiation includes X-rays, radiography, computed tomography (CT) scans, and nuclear medicine imaging techniques. These techniques are sometimes necessary for diagnosing acute and chronic conditions in pregnant patients. When used in small quantities, they are generally considered safe during pregnancy.

The potential risk to the fetus from ionizing radiation depends on the gestational age and the dose of radiation. If extremely high doses of radiation (over 1 Gy) are used during early embryogenesis, it is likely to be lethal to the embryo. In humans, the most common adverse effects from high-dose radiation exposure include growth restriction, microcephaly, and intellectual disability.

The use of CT scans during pregnancy has increased significantly in the United States, with nearly a four-fold rise over the last two decades. This is concerning because CT scans involve a large dose of ionizing radiation, exposing the fetus to potential harm.

Ultrasound and magnetic resonance imaging (MRI) are recommended as the imaging techniques of choice during pregnancy as they do not use ionizing radiation and are not associated with risk to the fetus. However, they should be used prudently and only when there is a relevant clinical question or medical benefit to the patient.

In summary, while ionizing radiation can be necessary for diagnosing certain conditions during pregnancy, it is important to carefully consider the risks and benefits. Ultrasound and MRI are generally safer alternatives and should be utilized whenever possible.

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