New clues to preterm delivery

RIGHT ON TRACK - Geologist Winston Seiler points out a set of prints made by a dinosaur as it walked through a wet, sandy oasis 190 million years ago in the Coyote Buttes North area straddling the Utah-Arizona border. Seiler and Marjorie Chan, chair of geology and geophysics at the University of Utah, published a study in the October issue of the journal Palaios showing that numerous impressions at the site are dinosaur tracks, not erosion-caused potholes as was previously believed. (university of utah/nicole miller via associated press)

DEPRESSION
Preterm delivery is the leading cause of infant mortality and one of medicine's most expensive challenges. Yet the root causes remain a mystery.

Now, new research suggests depression in pregnant women plays an important role.

The Kaiser Permanente Division of Research in Oakland, Calif., looked at 791 pregnant Kaiser Permanente members in the city and county of San Francisco from October 1996 through October 1998. Pregnant women were interviewed around their 10th week of pregnancy using a standardized, 20-question inventory widely used to measure depressive symptoms.

Researchers found that pregnant women with severe depressive symptoms have twice the risk of preterm delivery than pregnant women with no symptoms of depression. Women with less severe symptoms had a 60 percent risk. None of the women in the study were taking antidepressants.

Emerging research has demonstrated that "mood disorders, especially depression during pregnancy, may influence the levels of placental hormones and placental functions," writes Dr. De-Kun Li, a senior reproductive and perinatal epidemiologist at Kaiser Permanente. "Therefore, psychopathologies could be important risk factors for preterm delivery that have been overlooked."

Women with significant symptoms of depression during early pregnancy tended to be younger, unmarried, African-American, and have less education and lower income than their white counterparts. They were also more likely to have smoked, and less likely to have used vitamin supplements.

Yet even after controlling for these differences, the depression-preterm delivery association remained.
BOTTOM LINE: Doctors need to pay attention to depression among pregnant patients. "Anything we can do to reduce preterm delivery is important," Li said.
CAUTIONS: The study shows an association, not a mechanism, between depression and preterm delivery. Scientists haven't figured out how mind-brain mediated hormonal changes interact with the placenta.
WHAT'S NEXT: Li wants to see if antidepressant medication helps prevent preterm delivery among depressed women.
WHERE TO FIND IT: Online in the Oxford University Press's journal Human Reproduction, on behalf of the European Society of Human Reproduction and Embryology, 2008.

LEIGH HOPPER
OBERHOLZER