Genetic screening tests to identify 'carriers' of Thalassemia are already offered to all pregnant women, and in certain high risk areas, Sickle Cell Anaemia and Haemoglobin disorders are also genetically screened for. A 'carrier' is someone who can pass the condition on to their offspring, but who does not show symptoms of the condition themselves. If a pregnant woman is found to be a carrier of Thalassemia Sickle Cell Anaemia or a Haemoglobin Disorder, the baby's father may also be tested. If he is found to be a carrier as well, the foetus may then be tested using a prenatal diagnostic test.

Newborn babies can also undergo genetic screening. There are three inheritable conditions that newborn babies can be genetically screened for: Phenylketonuria (PKU), Cystic Fibrosis and Sickle Cell Anaemia through a 'heel prick' or 'blood spot' test whereby a small amount of blood is taken from the heel to be genetically tested. These tests can identify those babies who are carriers of these conditions as well as identifying those babies who will go on to develop them.

Genetic screening is different to some of the other screening tests offered in pregnancy, e.g. Down's Syndrome screening, as genetic screening involves the analysis of genes, whereas Down's Syndrome may be identified through a blood test (which looks for particular hormones and proteins rather than genes) and an ultrasound scan which measures the nuchal translucency (fluid at the back of the foetus' neck). Whilst Down's Syndrome is caused by the presence of an additional chromosome, it is not generally considered to be an inheritable condition, meaning that it does not run in families in the same way as other genetic conditions and so there is no screening for genetic 'carriers' of Down's Syndrome.