BMJ Study Find SSRIs During Pregnancy Double Risk of PPHNJan 13, 2012 | Parker Waichman LLP
A new study published in the British Medical Journal has provided compelling new evidence of a connection between selective serotonin reuptake inhibitors (SSRI) antidepressants and pulmonary hypertension of the newborn (PPHN). The study, conducted by researchers at Sweden's Karolinska Institute, found that babies exposed to SSRI antidepressants in-utero are two times as likely to be born with the life-threatening lung condition compare to those who aren't.
PPHN is caused when arteries leading to the lungs constrict upon birth, blocking blood flow and air to the vital organs. In about 10 percent of cases, it turns out to be fatal. The disorder affects about 1 in 1,000 births.
Some earlier studies have pointed to a connection between SSRI antidepressants - a class of medications that includes Prozac, Paxil, Celexa, Zoloft - and PPHN. In fact, in 2006 the U.S. Food & Drug Administration (FDA) issued a warning about SSRIs and PPHN in 2006, after a New England Journal of Medicine study found that women taking the drugs were six times more likely to deliver babies with PPHN. But last month, the FDA revised that warning, and told doctors to continue treating expectant mothers with SSRIs because the conflicting results different studies made it "premature to reach any conclusion about a possible link between SSRI use in pregnancy and PPHN.
This new study was based on 1.6 million births in Denmark, Finland, Iceland, Norway or Sweden from 1996 to 2007. The researchers took into account other factors, such as obesity, diabetes, or behaviors such as smoking, or the way the baby was delivered, that are known to be associated with the development of PPHN. Of the 30,000 women in the study who took SSRIs while pregnant, nearly 11,000 took the drugs during late pregnancy and about 17,000 took them during early pregnancy. Among the group who took SSRIs during late pregnancy, 33 babies (0.2 percent) were born with PPHN, the researchers found. In the group who took the drugs during early pregnancy, 32 (0.2 percent) PPHN babies were born.
"Infants born to women treated with SSRIs in late pregnancy had a twofold increased risk [of] their infants having persistent pulmonary hypertension," lead researcher Dr. Helle Kieler, head of the Centre for Pharmacoepidemiology at Karolinska University Hospital in Stockholm, wrote.
"The increased risk seemed to be a class effect of SSRIs, as risks for the specific SSRIs were of similar magnitude," she added.