By Olivia Scheck
DNAinfo Reporter/Producer
MANHATTAN — The trauma of the Sept. 11 attacks may have caused an increase in miscarriages among male babies throughout the nation, a study published Tuesday reported, while a previous study suggested the effect was especially severe in New York City.
The more recent study, conducted by researchers at the University of California, found the ratio of miscarried male fetuses compared to miscarried female fetuses was 12 percent higher than expected during September 2001.
Researchers blamed the "communal bereavement" hypothesis for the change, which claims that widespread grief — like the 9/11 terrorist attacks on the World Trade Center— can cause pregnant women to secrete stress hormones that are harmful to male fetuses after the 20th week, according to the study's authors.
There was not an apparent increase in miscarriages among female babies because female fetuses are not as susceptible to those same stress hormones, researchers said.
"Male fetuses are more sensitive to maternal stress hormones," Tim Bruckner, the study's lead author told DNAinfo, explaining why the findings suggested an increase in miscarriages.
Bruckner also referred to a 2006 study, which found an even larger effect among pregnant women within the city.
"[The effect in] New York City was particularly pronounced," he noted.
