Although most babies are healthy, approximately 2-3 every 100 babies may have an abnormality or condition for which the pregnancy would require specialist care. Some minor congenital problems do not pose risk to the baby and do not require treatment. Some congenital problems may require treatment during pregnancy or an operation soon after birth. Rarely there may be a severe problem which could be life-limiting or could cause significant disability. 

What does the anomaly scan involve?

This is a detailed inspection of the baby which is performed at 18-22 weeks but also later in pregnancy.

The scan takes 30-60 minutes. Although most structural problems will be identified, it is not as good as a nuchal scan at detecting Down's syndrome. The anomaly scan will be performed in detail and will allow a close look at the baby’s bones, heart, brain, spinal cord, face, kidneys, abdomen and other organs. You do not usually need a full bladder. You will get a report immediately after the scan and you will have the opportunity to ask any questions. We can tell you the baby's sex at this stage.

How accurate is the anomaly scan?

In experienced hands the anomaly scan will detect most congenital problems for which the baby would require specialist care. However not all congenital problems can be diagnosed on ultrasound. Some conditions can be detected very accurately, for instance more than 90% of babies with open spina bifida will be detected. At least 50% of babies with a heart defect can be detected before birth. There are some conditions that cannot be detected with ultrasound, such as autism or some genetic syndromes.

Mr Impey and Dr Ioannou are Consultants in Fetal Medicine with extensive experience in ultrasound. They care for most of the babies with serious structural abnormalities that are to be born in Oxford and are therefore well placed to perform this scan.