(NEW YORK) -- Pregnant women who take certain anti-depressants can significantly increase their chance of having babies that develop a condition known as pulmonary hypertension, according to a study published Thursday in the British Medical Journal.
An estimated one in every 1,000 babies born develop pulmonary hypertension, characterized by high blood pressure in the lung arteries, according to the American Academy of Pediatrics.
The condition occurs when newborn babies are not able to adapt to breathing on their own, which can potentially lead to organ failure and brain damage. On average, 11 percent of newborns diagnosed with this condition will die from it, according to the American Academy of Pediatrics.
The study suggests that women who took one of the most prescribed class of anti-depressant medications known as selective serotonin reuptake inhibitors (SSRI) during pregnancy were twice as likely to have their baby develop pulmonary hypertension compared with mothers who didn't take SSRIs.
But many experts said the risk is still low.
"You're doubling the risk of extremely low risk to again, an extremely low risk," said Dr. Marjorie Greenfield, division director of obstetrics and gynecology at University Hospitals Case Medical Center in Cleveland. SSRIs, more commonly known by their brand names such as Zoloft, Paxil, Celexa and Lexapro, are taken by 1.5 percent of pregnant women in the U.S.
The study reviewed six million births that took place from 1996 to 2007 in Denmark, Finland, Iceland, Norway and Sweden.
Study researchers said they took into consideration the mothers' health conditions such as obesity, diabetes, or behaviors such as smoking, or the way the baby was delivered. These factors have previously been associated to a baby's development of pulmonary hypertension.
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