Cindy Barkway holds her newborn son David in her Etobicoke home. Cindy's husband Michael Barkway was a victim of the attacks at The World Trade Center in New York. Getty Images

According to a new study released by the National Bureau of Economic Research in August, pregnant women living near the World Trade Centre during the 11 September attacks in the US, experienced higher-than-normal negative pregnancies.

Princeton University's Woodrow Wilson School of Public and International Affairs has reported that pregnant women living near the attack site were more likely to give birth prematurely and deliver babies with low birth weights.

The study, led by Wilson school's Janet Currie and Hannes Schwandt, further states that baby boys born to these women were more likely to have birth complications, low birth weights, and be admitted to neonatal intensive care units after birth.

Wilson School's Centre for Health and Wellbeing director, Janet Currie noted: "Previous research into the health impacts of in utero exposure to the 9/11 dust cloud on birth outcomes has shown little evidence of consistent effects. This is a puzzle given that 9/11 was one of the worst environmental catastrophes to have ever befallen New York City.

"Our work suggests a simple resolution of this puzzle, which is that the women who lived in neighbourhoods exposed to the 9/11 dust cloud had very different experiences than women in other parts of New York City."

Past studies have indicated that the collapse of the World Trade towers resulted in a zone of negative air pressure that was forced into close by neighbourhoods, including Lower Manhattan, Battery Park City, SoHo, TriBeCa, Civic Centre, Little Italy, Chinatown and the Lower East Side.

Some studies have also shown that adults exposed to the World Trade Centre dust cloud have had significant health issues.

The entire study titled, "The 9/11 Dust Cloud and Pregnancy Outcomes: A Reconsideration," can be accessed at the National Bureau of Economic Research.