But left untreated, depression may also increase the chance of preterm birth, says researcher Katherine Wisner, MD, professor of psychiatry, ob-gyn, and women's studies at the University of Pittsburgh Medical Center.
Each pregnant woman has to work with her doctor to weigh the benefits and risks of treatment with antidepressants known as selective serotonin reuptake inhibitors (SSRIs), she says.
The new study, presented at the annual meeting of the American Psychiatric Association, involved about 200 pregnant women. About half of them suffered from depression, and half of those women took SSRIs throughout pregnancy.
Results showed that 23% of those who took SSRIs throughout pregnancy gave birth to preterm babies. But so did 21% of those with depression who didn't take SSRIs -- a difference so small it could be due to chance.
In contrast, only 6% of women who did not have depression and didn't take SSRIs had preterm babies.
According to Wisner, other research had shown that both depression and SSRIs can raise the risk for miscarriage. But taking antidepressants during pregnancy doesn't greatly increase the overall risk of most birth defects, she says.
Ambien and Pregnancy
Further follow-up showed that women taking Ambien were slightly, but not significantly, more likely to give birth to preterm or low-birth-weight babies.
"Further study is needed to determine whether Ambien or the sleep disturbances caused adverse outcomes," says Jeff Newport, MD, a psychiatrist at Emory.
Temple University's David Baron, DO, chairman of the committee that chose which studies to highlight at the meeting, says he urges his patients to try non-pharmaceutical methods of easing sleep before turning to medication.
"But sometimes the symptoms [of insomnia] are more noxious than the drug," he tells WebMD.