Understanding Your 20-Week Anatomy Scan
What the 20-week anatomy scan checks, how to prepare, and what results mean for you and your baby.
The 20-week anatomy scan is one of the most anticipated and emotionally significant appointments of your entire pregnancy. It's the appointment where many parents find out whether they're having a boy or a girl, but far more importantly, it's a comprehensive check-up that looks in remarkable detail at how your baby is growing and whether all the major organs and structures are developing exactly as they should be.
What Exactly Is the Anatomy Scan? ๐ฅ๏ธ
Also called the mid-pregnancy ultrasound, the level 2 ultrasound, or the anomaly scan, this detailed examination is typically scheduled between weeks 18 and 22 of pregnancy. A specially trained sonographer uses high-frequency sound waves to create detailed images of your baby from multiple angles. The appointment usually takes between 30 and 45 minutes, though it can occasionally take longer if your baby is in an uncooperative position, which they often are!
What Does the Sonographer Check? ๐
The level of detail in this scan is genuinely remarkable. The sonographer will carefully examine your baby's brain and spinal cord, all four chambers of the heart and major blood vessels, kidneys and bladder, stomach and abdominal wall, face and lips (specifically checking for cleft lip), arms and legs and their bones, fingers and toes, and the umbilical cord. They'll also assess your placenta's position, check your amniotic fluid levels, and confirm your baby's measurements to verify the due date.
Finding Out the Sex ๐ถ
If your baby is in the right position and you'd like to know the sex, this is typically when you'll find out. The sonographer will ask you before the scan whether you want to know. If you'd prefer a surprise, simply say so and they'll carefully avoid revealing it. Some parents ask for the information to be written in a sealed envelope for a gender reveal celebration later, just ask your clinic if they offer this option.
What If Something Looks Unusual? ๐
Please try not to panic if the sonographer says they need to look more closely at a particular area or wants to repeat a measurement. This is extremely common and usually simply means your baby was in an awkward position or the image quality wasn't quite clear enough. If there is a genuine finding of concern, you will be referred for a more detailed scan with a specialist or a maternal-fetal medicine doctor. The vast majority of so-called 'soft markers' turn out to be completely insignificant.
How to Prepare for the Appointment ๐
Unlike earlier pregnancy scans, you generally don't need a full bladder for the 20-week anatomy scan. Wear comfortable, loose-fitting clothing that gives the sonographer easy access to your belly. Eating a meal or snack beforehand can encourage your baby to be more active and potentially move into a better position. And please, bring your partner, a family member, or a close friend, this is genuinely one of the highlights of pregnancy.