Increased levels of corticotropin-releasing hormone (CRH), which is produced by the placenta, identifies women who are at risk for developing depression after their pregnancy ends, according to a study in the Archives of General Psychiatry as quoted by media Tuesday.

"The high incidence and severe consequences of postpartum depression make the identification of women at risk an important research goal," Dr. Ilona S. Yim at the University of California, Irvine, and co-investigators write in their report.

They point out that several lines of evidence link CRH, a key hormone involved in regulating many other hormones, to depressive symptoms following delivery.

Furthermore, the researchers conducted a study in which hormone levels in the blood were measured several times throughout pregnancy in 100 women, starting at week 15. Sixteen women developed postpartum depression.

Placental CRH level at 25 weeks was a strong predictor of postpartum depression, the authors report.

Yim's group suggests that screening for placental CRH is a plausible means of predicting postpartum depression.

"Because blood draws to screen for gestational diabetes are typically performed at 24 to 28 weeks gestational age," they write, "a potential postpartum depression screen could be completed at the same time."

(Agencies via Xinhua News Agency February 3, 2009)