Your 20 week scan

At around 18 to 20 weeks into pregnancy, you will be offered an ultrasound screening. The main purpose of this scan is to check that your baby is developing normally. This is also the scan when you can choose to find out if you’re expecting a boy or a girl, and you have a chance to get some new photographs of your baby.

This scan is usually called the ’20 week scan’, but its proper name is the ‘fetal anomaly screening’, because it checks for structural abnormalities in your baby’s growth – including the heart.

Just like your 12 week dating scan, the 20 week scan uses ultrasound, which sends high-frequency sound waves through your uterus which then bounce off your baby and produce an image on a computer screen. Ultrasound is not harmful or invasive to your baby or to you.

Your appointment should take at least 30 minutes as there are a number of different views of your baby that your sonographer will want to check.

Who will be with me during my scan?

Your scan will usually be performed by a sonographer, and sometimes by an obstetrician. You will normally be able to take your partner, or one friend or family member along to the scan – but other children are not usually allowed.

Screening my baby’s heart

Every pregnancy has a small risk of a problem with the developing baby. Twenty weeks into pregnancy is the best time to screen your baby’s heart, and your sonographer will want to look at various views of the heart to check for any problems. If a congenital heart defect is present, it is more likely to be seen at this point, which is why we recommend learning enough about your scan and CHD to be able to discuss your baby’s heart health with your sonographer. Our information card will help you do that.

Why your 20 week scan is so important

First of all, it can be a very exciting experience and a great opportunity to find out more about your baby before you’ve met them. But, in terms of screening your baby’s heart in particular, your 20 week scan is absolutely invaluable. Detecting heart problems before birth has huge benefits. It allows appropriate care of mum and baby before birth, and allows doctors to plan for a safer delivery in the right place, at the right time, and under the right conditions. Should a problem be found, earlier detection allows the parents to learn more about their baby’s condition and prepare for whatever treatment and care is needed. Detecting congenital heart defects after birth can be difficult and some heart conditions can be life-threatening if not dealt with appropriately and as soon as possible. Research shows early detection increases the baby’s survival chances, and helps their longer-term quality of life – so, if a baby has a heart problem, the sooner it is spotted, the better.

What happens if a problem is suspected?

If your sonographer suspects a heart defect, they will refer you to a specialist fetal cardiologist for an appointment to take a more detailed scan. This appointment should take place no longer than five working days after your 20 week scan.

Finding out there may be a problem with your baby’s heart is a very tough and worrying time. It’s completely natural to want to do something and find out as much information as possible. However, heart conditions are often very complicated and no two patients are exactly the same – only your specialist can offer the most accurate diagnosis. Whatever the outcome, the specialist will be able to answer all your questions and help you to plan the next steps.