Screening for a potentially lethal disease that is not clinically apparent seems intuitively worthwhile. However, the controversies regarding screening for presymptomatic breast or prostate carcinoma, which have raged both in the popular and medical media, illustrate that this can be a vexed subject. The journey to date for prenatal screening for major congenital heart disease (mCHD) has likewise not been straightforward.

When prenatal screening for mCHD was first suggested more than 30 years ago, it was anticipated that high-risk pregnancies, such as those with family history of heart defects, could be targeted.1 However, it soon became evident that most mCHD detected prenatally was to be diagnosed because the front-line fetal ultrasonographer suspected a cardiac abnormality at the mid trimester anomaly scan in pregnancies not previously designated as high risk.2 Population-based screening was advocated, initially on the basis of the four-chamber view of the fetal heart, obtained from a transverse imaging section of the fetal thorax, with the subsequent addition of outflow tract views in more recent guidelines.3

Prenatal detection of mCHD confers two potentially beneficial opportunities:

• provision of time for preparation by parents and professionals, including the consideration of termination of pregnancy, and

• perinatal management of the neonate with mCHD in an environment where the required expertise is available.

The value of counselling to inform considered decision-making, which includes options of invasive fetal chromosome analysis, termination of pregnancy and plans for postnatal management, should not be underestimated. It is …