Low-income pregnant women and new mothers with diabetes have nearly twice the risk of experiencing depression during and after pregnancy than women without diabetes, according to a study in the February 25 issue of JAMA.

Depression during the perinatal period (often considered as the last several months of pregnancy and the year following childbirth) affects at least 10 percent to 12 percent of new mothers, and approximately 2 percent to 9 percent of pregnancies are complicated by diabetes, according to background information in the article. Prior studies have established an association between diabetes and depressive disorders in general adult populations.

Katy Backes Kozhimannil, M.P.A., of Harvard Medical School and Harvard Pilgrim Health Care, Boston, and colleagues examined the association between diabetes and depression in the perinatal period among low-income women. The researchers used data from New Jersey's Medicaid administrative claims database, and included 11,024 women who gave birth between July 2004 and September 2006, and who were continuously enrolled in Medicaid for 6 months prior to delivery and 1 year after giving birth.

The researchers found that women with any form of diabetes were significantly more likely to experience some indication of depression during pregnancy or postpartum. After controlling for the effects of age, race, year of delivery, and preterm birth, women with diabetes had nearly double the odds of having a depression diagnosis or taking an antidepressant medication during the perinatal period (15.2 percent) compared with those who had no indication of diabetes (8.5 percent). This association remained consistent across the various types of diabetes.

Among women with no indication of depression during pregnancy, those with diabetes had higher odds of experiencing new onset depression during the postpartum period (9.6 percent) compared with those without diabetes (5.9 percent).

"Pregnancy and the postpartum period represent a time of increased vulnerability to depression. Treatable, perinatal depression is underdiagnosed, and it is important to target detection and support efforts toward women at high risk," the authors write.

"… studies designed to test the impact of interventions that target those most vulnerable to depression during the perinatal period could provide helpful input to policy making. Among all women with depression, diabetes, or other mental or physical health conditions that complicate the normal course of pregnancy and postpartum recovery, careful monitoring and appropriate treatment are critical to ensuring the health of the mother and her child."