Skip to content

Men's Health

Font Size

Paternity Study Shakes Up the Family Tree

British Researchers Look at How Many Dads Are Unknowingly Raising Another Man's Child
WebMD Health News

Aug. 10, 2005 -- New British research is rattling the roots of the family tree, citing paternity "discrepancy" in perhaps 4% of fathers studied.

"Paternal discrepancy" is a delicate term for a loaded subject. It refers to a man who wrongly thinks he's a child's biological father.

Paternal discrepancy was studied by researchers including Professor Mark Bellis, director of the Centre for Public Health at Liverpool John Moores University in England. Their findings appear in the Journal of Epidemiology and Community Health.

Daddy Discrepancy

Bellis and colleagues checked studies from the 1950s through 2002 that mentioned paternal discrepancy. The studies came from the U.K., U.S., Europe, Russia, Canada, South Africa, South America, New Zealand, and Mexico.

Over the years, few studies directly tackled the topic. For instance, some researchers set out to screen for multiple sclerosis or cystic fibrosis, noting paternal discrepancies along the way.

Some studies were large; others included a handful of people. Paternal-discrepancy estimates varied wildly, from less than 1% to more than 30%.

But those numbers don't tell the whole story.

Some research centered on paternity disputes. Daddy discrepancies were probably overrepresented in those studies, writes Bellis.

Setting those studies aside, the remaining research showed an average paternal discrepancy of 3.7%, or a little less than one in 25 dads, write the researchers.

Don't Jump to Conclusions

That number doesn't necessarily mean that out of 25 dads at the ballpark, one isn't really his child's biological father.

Because the researchers extrapolated some information from studies involving topics other than paternity, they say that the percentage is not a true indication of paternal discrepancies in the general population. However, "it does suggest the widely used (but unsubstantiated) figure of 10% paternal discrepancy may be an overestimate for most populations," write the researchers.

In other words, paternal discrepancy might be rarer than commonly thought.

Rates were higher for disadvantaged people, for those with more than one sex partner at a time, and for younger women, write the researchers. "No clear population measures of paternal discrepancy are currently available," they note.

Today on WebMD

man coughing
Men shouldn’t ignore.
man swinging in hammock
And how to get out it.
shaving tools
On your shaving skills.
muscular man flexing
Four facts that matter.
Food Men 10 Foods Boost Male Health
Thoughtful man sitting on bed
Man taking blood pressure
doctor holding syringe

Loaded with tips to help you avoid food allergy triggers.

Loading ...

Sending your email...

This feature is temporarily unavailable. Please try again later.


Now check your email account on your mobile phone to download your new app.

Condom Quiz
man running
older couple in bed