What to Expect During an Anatomy Scan

Somewhere around the midpoint of pregnancy comes an especially exciting (and maybe a little nerve-wracking) appointment: your anatomy scan! It's when a sonographer takes a close look at your baby's brain, heart, kidneys, and spine—and when you'll likely get your best glimpse yet at those tiny fingers and toes. Here's what happens on the table and how to make sense of the results.

What is an anatomy scan?

An anatomy scan—also called a "level II," "detailed," or mid-pregnancy ultrasound—is a specialized sonogram typically done between 18 weeks and 22 weeks of pregnancy. It’s a comprehensive, head-to-toe survey of your baby's organs and body structures, plus a check of your placenta, umbilical cord, and amniotic fluid.

Medical societies classify prenatal ultrasounds as standard, limited, or specialized (detailed). A standard second-trimester ultrasound, done in low-risk pregnancies, checks fetal development, screens for major structural differences, and estimates gestational age. A detailed "level II" scan goes further and is reserved for pregnancies where the standard scan or your health history warrants a closer look.

Why are anatomy scans done?

Anatomy scans are done to check that your baby's organs are developing as expected, and to catch potential concerns early enough to plan for them. In the United States, about 1 in 33 babies is born with a birth defect, and this ultrasound is one of the main tools providers use to look for physical differences before birth—giving you time to line up specialists or plan your delivery if needed. It also double-checks your due date, confirms how many babies you're carrying, and evaluates your placenta's position.

What happens during an anatomy scan?

A sonographer applies gel to your belly and moves a transducer across your abdomen. The probe sends out sound waves that bounce off your baby and surrounding structures, creating the images you see on screen—the same technology as earlier ultrasounds, just longer and more methodical. The sonographer captures specific views (heart chambers, brain, facial profile, limbs, abdominal organs, spine, cord insertion point) along with growth measurements. The appointment typically takes 30 to 60 minutes, but if your baby is in an awkward position, you may need a follow-up look.

What do doctors learn from an anatomy scan?

The scan tells your care team whether your baby's organs and structures look typical for their gestational age: the brain and spine (including a check for neural tube differences like spina bifida), the heart's chambers, the face (screening for cleft lip or palate), the abdominal organs, the limbs, and the placenta and amniotic fluid. It also reveals growth trajectory, and if you'd like, the sonographer can usually tell you the sex. (For more on this stage, see our 20 weeks pregnant guide.)

What should I expect during my appointment?

Plan for a low-key but longer-than-usual visit. You likely won't need a full bladder this time! Bring a partner if you can—many people find this scan more emotional than earlier ones, since you'll see a genuinely baby-shaped figure movin’ and groovin’. The sonographer usually won't narrate findings in real time—a radiologist or maternal-fetal medicine specialist reviews the images and then they or your provider will share the results (it’s possible you’ll need to wait until your next visit).

What do my anatomy scan results mean?

Results generally fall into a few buckets:

• Normal: Everything typical for gestational age
• Incomplete: A structure couldn't be clearly seen, warranting a follow-up
• Soft markers noted: a common, usually harmless variant that may prompt added monitoring
• Structural difference identified: typically means a referral to a maternal-fetal medicine specialist

Remember, an anatomy scan is a screening tool, not a diagnostic one—it flags things worth a closer look but doesn't provide a definitive diagnosis for most conditions.

What conditions can an anatomy scan detect?

A detailed second-trimester ultrasound can identify:

• Neural tube defects (like spina bifida)
• Congenital heart defects
• Cleft lip or palate
• Abdominal wall defects
• Kidney anomalies
• Skeletal differences

It can also flag markers associated with, though not exclusive to, chromosomal conditions like Down syndrome—one reason some people pair it with prenatal genetic testing.

Detection rates vary by condition. A 2024 Cochrane review pooling data from more than 7 million fetuses found a single second-trimester scan detected roughly half of structural anomalies overall, while combining first- and second-trimester scans meaningfully improved detection—a reminder that anatomy scans are powerful but not a guarantee of catching every condition before birth.

Will I need additional tests after my anatomy scan?

Not usually. Most people move on without further imaging. But your provider may suggest more testing if the scan was incomplete, a soft marker was noted, or you have risk factors like advanced maternal age or a family history of a genetic condition.

Follow-up options might include:

• Repeat ultrasound
• Fetal echocardiogram
• Diagnostic testing like amniocentesis
• Referral to a specialist or genetic counselor

What questions should I ask during my anatomy scan?

It's reasonable to want context in the moment, even knowing full interpretation comes later. During the scan, ask whether the sonographer saw everything on the checklist and where your placenta is located. At your follow-up appointment, ask whether all structures fell within the expected range, whether any soft markers were noted, and whether additional testing is recommended.

The Bottom Line

The anatomy scan is one of the more memorable milestones of pregnancy—part medical checkpoint, part first real glimpse of your baby's face and full body. For most people, it's a reassuring appointment that confirms development is on track. And if it turns up a question mark, catching it now gives you and your care team time to plan next steps together.

More on Prenatal and Postnatal Care:

• What to Know About the Group B Strep Test During Pregnancy
• Everything You Need to Know About Glucose Screening in Pregnancy
• Your Prenatal Appointment Schedule
• What to Expect at Your Postpartum Checkup

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• The American College of Obstetricians and Gynecologists: Ultrasound Exams
• Sonography Fetal Assessment, Protocols, and Interpretation, StatPearls, Apr 2026
• Centers for Disease Control and Prevention: Screening for Birth Defects
• National Library of Medicine: Pregnancy Ultrasound
• Centers for Disease Control and Prevention: Diagnosis of Birth Defects
• Diagnostic Accuracy of Ultrasound Screening for Fetal Structural Abnormalities During the First and Second Trimester of Pregnancy in Low-Risk and Unselected Populations, Cochrane Database of Systematic Reviews, May 2024

Disclaimer: The information on our site is NOT medical advice for any specific person or condition. It is only meant as general information. If you have any medical questions and concerns about your child or yourself, please contact your health provider.