(USA TODAY) -- Pregnant women who are depressed are generally told that continuing their medication will help them and their baby. A mother who is too sad won't take good care of herself, and the baby will suffer, the thinking goes.

But a new review of the scientific literature questions the assumption that depression is bad for a fetus, and it concludes that antidepressants often confer more risk than benefit.

"There's clear and concerning evidence of risk with the use of these medications by pregnant women," says Adam Urato, a chairman of the department of Obstetrics & Gynecology at MetroWest Medical Center in Framingham, Mass., and one of the authors of the paper published in the journal Human Reproduction.

Despite decades of antidepressant use, no one has ever done the kind of research that would definitively answer the safety question: following the pregnancies of two groups of depressed women, half on medication such as Prozac, Paxil, Lexapro, Celexa and Zoloft, half not.

That kind of research would be extremely expensive and ethically questionable, Urato says, because so many studies link antidepressants to miscarriage, preterm birth, rare heart defects and behavioral problems.

More controversially, Urato and co-author Alice Domar, a Harvard Medical School assistant clinical professor, also say antidepressants have little or no benefit for pregnant women. Domar, an infertility expert, says a form of talk therapy known as cognitive behavioral therapy is just as effective.

Many experts disagree, however.

"I would say the authors of this article went overboard in terms of their negativity," says Gregory Moore, director of health services at Georgia Tech in Atlanta and a member of the American College of Obstetricians and Gynecologists' committee on ethics. "Depression can be a fatal disease."

The decision whether to use antidepressants during pregnancy should be between a woman and her doctor, says Shari Lusskin, an adjunct associate professor at Mount Sinai School of Medicine in New York City.

Drug companies that make the antidepressants declined to comment or did not respond to e-mail requests. An industry group, the Pharmaceutical Research and Manufacturers of America, says the federal drug approval and review process is designed to guarantee drug safety.

Kimberly Yonkers, a Yale University psychiatrist and an expert on women's mental health, says she agrees with Domar and Urato that a mother's depression is not inherently bad for a fetus. And pregnant women with mild to moderate disease may do OK weaning themselves off antidepressants.

But women who consistently relapse when they go off antidepressants should be confident that taking antidepressants is best for them and their baby, she says.

"It's a dangerous message for women who are pregnant and depressed to say that antidepressants don't benefit them," Yonkers says.

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