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Up To One In Twenty-five Dads Are Not The Real Father


The constantly increasing use of paternity tests for medical and legal purposes means more couples are discovering the biological proof of who fathered the child. The team at Liverpool John Moores University based their estimate on research findings published between 1950 and 2004.

Paternity Tests Becoming More Common

The implications of so-called paternal discrepancy were huge and largely ignored, even though the incidence was increasing, according to Professor Mark Bellis and his team. In the US the number of paternity tests increased from 142,000 in 1991 to 310,490 in 2001. The demand for these tests and similar testing has grown by a factor of 10 in the last decade in the UK, with the current level in the UK at somewhere between 8,900 and 20,000 tests per year.

Various Reasons For Paternity Tests

About 5,000 of these paternity DNA tests are requested by the Child Support Agency (CSA) to resolve child maintenance disputes. Other tests are conducted to investigate inherited health disorders and others for social reasons. The Liverpool team found that rates of paternity tests where a father was proven not to be the biological father of his child ranged from 1% in some studies to as much as 30%, though experts have generally agreed that the rate is below 10%, with a 4% rate meaning that about one in 25 could be affected. However, increasing use of genetic testing is likely to boost the rates of paternal discrepancy, say the authors.

Paternity Tests – Important Consequences

Professor Bellis said that the effect on a man who discovers he is not the biological father of a child could be devastating. It can lead to relationship breakdown, mental health problems for both partners and even domestic violence, while the children involved can experience low self-esteem and anxiety.


The NSPCC said fathers who find out after the test that they have been raising another man’s child should remember that however angry they feel, it must not be taken out on the child in any way. “The child will still regard the parent as their father. Rejection could be a devastating double blow for the child, ” said a spokeswoman.

Counselling after paternity tests is available for distressed parents and children alike. There are various organisations listed on our help and support page.