A study from Liverpool John Moores University in the UK has found up to 1 in 25 fathers are unknowingly raising another man's child.
The research, reported in the Journal of Epidemiology and Community Health, was drawn from studies of men and women wanting proof of paternity from testing as well as studies based on genetic health screening. The researchers in Liverpool found that rates of cases where a man was not the biological father of his child ranged from 1% in some studies to as much as 30%.
Experts have generally agreed the number of men unknowingly bringing up a child they believe to be their own is below ten per cent. A rate of four percent would mean one in 25 families is affected.
The Liverpool research headed by Professor Mark Bellis, looked at data from the UK, U.S., Canada, Europe, Russia, South Africa, South America, Mexico and New Zealand. In the US, the number of paternity tests have increased from 142,000 in 1991 to 310,490 in 2001. In the UK the estimated number of paternity tests are between 8,900 and 20,000 tests per year.
Careful when interpreting the results
One in 25 sounds worrying. Can it really be true that so many fathers are bringing up other men's children?
The study does not mean that when you look around in a crowd that 1 in 25 men are in that situation. The range of research findings did show big variations in rates, from one per cent in some studies to nearly 30 per cent. The figures did vary by country and groups; for instance, rates were higher for disadvantaged people, for those with more than one sex partner at a time, and for younger women.
Reasons for mistaken paternity
Paternal discrepancy could stem from infidelity or it could be that a change of partner leads to genuine mistaken paternity.
Paternity testing is simple and involves taking a swab from the inside of the mouth or from a blood sample. Coping with the test results is a different matter. Often even basic counseling is not provided to help people cope and manage the information.
The health repercussions for men finding they are not the biological parent of a child can be substantial. Stress, mental health problems, domestic violence to the partner and child.