Pregnancy comes with several ultrasounds, and two of them often get confused: the anomaly scan and the fetal echocardiogram. Both are safe and painless, and both usually happen in the second trimester (between 18 and 24 weeks). They answer different questions, though. Knowing the difference helps you understand why your doctor recommends one or both.
What Is an Anomaly Scan?
An anomaly scan, also called a level 2 ultrasound or targeted scan, is a detailed check of the baby’s overall development. It is usually done between 18 and 22 weeks. The sonographer examines the brain, spine, face, chest, abdomen, kidneys, and limbs. The placenta position, amniotic fluid level, umbilical cord, and baby’s growth are checked as well.
This scan is routinely advised for all pregnant women, whether or not they have risk factors. It includes basic views of the heart, but it is not a dedicated heart assessment.
What Is a Fetal Echo Scan?
A fetal echocardiogram is a specialised ultrasound focused only on the baby’s heart. It looks closely at the four chambers, valves, major blood vessels, blood flow, and heart rhythm, often using Doppler imaging. It is generally performed between 18 and 24 weeks, when the heart is large enough to be seen in fine detail.
A fetal medicine specialist or paediatric cardiologist usually carries it out, and it can take 30 to 45 minutes.
Key Differences at a Glance
| Aspect | Anomaly Scan | Fetal Echo |
| Scope | Reviews the whole baby | Studies the heart alone |
| Who needs it | Routine for everyone | Advised when there is a specific reason |
| Level of detail | Checks basic heart views | Examines structure, blood flow, and rhythm in depth |
| Expertise | Performed by a trained sonographer or radiologist | Needs a specialist trained in fetal cardiac imaging |
Who May Need a Fetal Echo?
Congenital heart defects affect roughly 1 in 100 babies, and many occur in pregnancies with no known risk. Even so, a fetal echo is commonly recommended in these situations:
- A parent or sibling has a congenital heart condition
- The mother has diabetes that was present before pregnancy
- The mother has an autoimmune condition such as lupus
- The baby was conceived through IVF
- Certain medicines or infections were involved early in pregnancy
- The anomaly scan or nuchal translucency scan suggested a possible heart concern
- The baby has an irregular heartbeat
- The pregnancy is a monochorionic twin pregnancy
Can One Replace the Other?
No. An anomaly scan can miss subtle heart problems, which is why a fetal echo scan is added when there is concern. A fetal echo, on the other hand, does not assess the brain, spine, kidneys, or other organs. The two scans work best as partners. It is also worth knowing that no prenatal scan can detect every condition, and image quality can be affected by the baby’s position or the mother’s body build.
What Should You Expect?
Both scans are non-invasive and use sound waves, not radiation. A gel is applied to the abdomen, and a probe is moved gently over it. You do not need to fast, and there is no recovery time. Your doctor will explain the findings afterwards. If something unusual appears, the next steps may include a repeat scan, further testing, or a consultation with a genetic counsellor or paediatric specialist. An unusual finding does not always mean a serious problem, so it is best not to conclude without speaking with your doctor.
Final Thoughts
The anomaly scan gives a broad overview of your baby’s development, while the fetal echo scan looks closely at the heart. If your obstetrician suggests a fetal echo, it is usually a precaution, not a sign that something is wrong. Ask your doctor which scans suit your pregnancy, and go through the results with a qualified specialist.
