A mixed blessing.

An ante-natal blood test designed to indicate the possibility of Down's syndrome in the foetus is the subject of this programme. The aim of the test is to make diagnosis of Down's syndrome more widely available. Hitherto, the only test for this condition was amniocentesis, which is a definitive test but involves a risk of miscarriage and is usually restricted to older women who are considered to have a higher risk of giving birth to a Down's syndrome child. The blood test can be carried out at 16 weeks of pregnancy, and in the case of a positive result the patient can have amniocentesis, with the option of termination of pregnancy should this confirm the positive result of the blood test. Here, the reactions of three couples to a positive blood test are shown. They express confusion over the statistics in which the degree of risk is expressed; they discuss the anxiety resulting from the test and the pressure on them to proceed to amniocentesis. Most women who get a positive result from the blood test go on to have normal babies. Is the test worth the worry? It is defended by Prof. Nick Ward (St. Bartholomew's Hospital, London) who pioneered it.