The heel prick test is a blood screening test that is offered to all newborn babies, and is usually taken before the baby is a week old.
As its name suggests, the baby's heel is pricked with a small needle. Drops of blood are then put onto a collection card – known as a Guthrie card – which is taken away and examined for genetic disorders including cystic fibrosis and sickle cell disease; as well as enzyme and thyroid deficiencies.
Additionally, since March 2009, babies have also been screened for the presence of MCADD, a rare disorder that affects the way the body converts fat into energy.
The heel prick test is an easy and efficient test, and is normally undertaken by a health visitor on one of their regular visits to a mother and her newborn. However, if the baby is taking antibiotics, the test will be delayed to guard against false results.
Experts believe that the test is not overly painful for the newborn. Some may cry when the test is taken, although this is usually just a brief reaction and the baby will usually settle very quickly.
Although the heel prick test is strongly recommended, the parents of the baby can decline to give their permission for the test to be taken.