A Happier Pregnancy for Depressed Women
Psychiatric medications taken during pregnancy are less risky than previously feared| From Explorations | By Vicky Waltz
Allen Mitchell, director of BU’s Slone Epidemiology Center, has led a landmark, decades-long study of birth defects. Photo by Vernon Doucette
When Diane Knight was seventeen, she was diagnosed with bipolar disorder, a manic-depressive illness characterized by extreme mood swings. Her doctor prescribed Celexa, an antidepressant, and perphenazine, a mood stabilizer, to help reduce her manic episodes, and she has taken the drugs ever since. Knight is now thirty-four, married, and ten weeks pregnant with her first child.
Women like Knight ⎯ who is among the 8 to 20 percent of pregnant women affected by clinical depression ⎯ have always faced a difficult choice. They can take antidepressants and risk the slight possibility of having a baby with a birth defect, or they can forgo treatment and risk a relapse.
“I really didn’t know what I should do,” says Knight (not her real name). “I like to do things naturally, and I really wanted to have a pregnancy that was not influenced by medication. But my husband, my doctors, and I decided that because I have a history of hospitalization, it would be safer for me to take my medication throughout my pregnancy.”
Research conducted by scientists at the Slone Epidemiology Center at Boston University may help pregnant women with depression sleep a little easier. In an article published last year in the New England Journal of Medicine, Allen Mitchell, a School of Public Health professor of epidemiology and a School of Medicine professor of pediatrics, found that taking antidepressants during pregnancy does not greatly increase the overall chance of birth defects, although taking specific antidepressants could slightly increase the possibility of certain abnormalities.
The results should be reassuring for most pregnant women who take antidepressants, says Mitchell, director of the Slone Epidemiology Center and the principal investigator on a long-term study of birth defects and drug use in pregnancy. “Mothers who took antidepressants while pregnant were at no higher risk for most defects than women who did not take antidepressants,” he says.
BU researchers looked at popular antidepressants in a class of drugs called selective serotonin reuptake inhibitors (SSRIs), which includes Zoloft, Paxil, Prozac, and Celexa, that were used during the first trimester of pregnancy. In their study of nearly 10,000 infants born with birth defects and nearly 6,000 healthy infants, they concluded that women who took sertraline (Zoloft) during pregnancy were twice as likely to have babies born with certain heart defects, and women taking paroxetine (Paxil) had more than three times the risk for one of those defects. While the results sound alarming, the rate of the defects is so low that a doubled risk represents a very small number, proportionally speaking, Mitchell says.
“The specific heart defects that were linked to sertraline and paroxetine, for example, occur in about 5 out of 10,000 babies, so a doubling of that risk means they occur in 10 out of 10,000 babies, and a tripling means they would occur in 15 out of 10,000,” he says. “So even a tripling of the risk still amounts to a very small chance that a baby will be born with one of the defects linked to these drugs.”
Of course, Mitchell continues, mothers-to-be must be made aware that antidepressants can pose a slight threat to the fetus. But they should also take into account that depression, particularly severe depression, can also cause damage. “There is evidence that links anxiety and depression to premature births and other adverse pregnancy outcomes,” he says. “Depressed people are more likely to have sleep disorders, poor diets, and poor exercise habits, all of which can be harmful to a fetus.”
The SSRI study, pioneered by Mitchell in 1975, is part of the Slone Epidemiology Center’s research into birth defects, an ongoing project with a database currently containing information on more than 32,700 mother-child pairs. Since 1975, the center has played a leading role in assessing the risks of birth defects in relation to medications taken during pregnancy, testing existing hypotheses, and identifying previously unsuspected associations.