MONDAY, Feb. 2 (HealthDay News) -- Measuring the levels of a hormone produced by the placenta during pregnancy might predict whether a woman is likely to develop postpartum depression, a new study suggests.

Approximately 13 percent of women will experience postpartum depression, a condition that holds significant consequences not only for women but for their infants and families as well, experts say. Once a woman has had postpartum depression, she is more likely to have future bouts of depression, and that puts infants and children at risk for cognitive, behavioral and social problems.

"If we know early on that a woman is at high risk to develop postpartum depression, then we can implement interventions before symptoms actually occur," said lead researcher Ilona S. Yim, an assistant professor of psychology at the University of California, Irvine.

"By means of a simple blood draw, we could correctly identify 75 percent of women who would later develop postpartum depression," she said.

The report is published in the February issue of Archives of General Psychiatry.

For the study, Yim's group looked for a link between placental corticotropin-releasing hormone (pCRH) and postpartum depression. The researchers took blood samples from 100 pregnant women at various stages during their pregnancy and tested for levels of pCRH.

They also assessed the women for signs of depression during pregnancy and about eight weeks, on average, after delivery.

In all, 16 women developed postpartum depression. In each case, the women had had high levels of pCRH at 25 weeks into their pregnancies, the study found.

The blood test, which was found to have a high degree of both specificity and sensitivity, could identify about 75 percent of women who would develop postpartum depression, Yim's team found. The test misclassified about 25 percent of the women.