Dad's Ethnicity May Influence Baby's Birth Weight

A father's ethnic background might influence how much his baby weighs at birth, a new study suggests.

These findings are more than simply intriguing, because a baby's birth weight is considered a measure of overall health. And, a lower than expected weight can trigger medical interventions, such as a Cesarean delivery, the researchers explained.

Plus, current birth weight guidelines are based on parents of Western European descent. This means that many babies of East Asian or South Asian parents may be considered underweight, even though they are normal for their ethnic groups.

The current study included data from almost 695,000 live births in the Canadian province of Ontario between 2002 and 2009. The researchers found that babies born to a foreign-born father and foreign-born mother weighed about 6 percent less than those born to two Canadian-born parents.

Babies born to a foreign-born father and Canadian-born mother weighed quite a bit less than those born to two Canadian-born parents, while babies born to a Canadian-born father and a foreign-born mother weighed somewhere in between, according to lead researcher Dr. Joel Ray, of St. Michael's Hospital in Toronto.

The findings suggest a link between a father's ethnicity and the birth weight of his child, but did not prove a cause-and-effect relationship.

Previous research by Ray found that a mother's ethnic background also affects her baby's birth weight.

The new study also found that babies' birth weights may be affected by where their parents currently live. Babies born to parents who lived in neighborhoods with a concentration of people from their same ethnic background had lower birth weights than babies of Canadian-born parents.

This was particularly true for male babies, according to the study released online June 29 in the Journal of Epidemiology and Community Health.

More information

The U.S. National Library of Medicine has more about birth weight.