February 4, 2015 — Women with severe maternal depression often begin to develop symptoms during pregnancy, not in the postpartum period, as is commonly thought, according to a new study, the New York Times' "Well" reports.
The study, published in Lancet Psychiatry, involved more than 8,200 women from 19 centers in seven countries. It is the largest to date on postpartum depressive symptoms, according to Leah Rubin, a co-author of a commentary on the study and an assistant professor in the Women's Mental Health Research Program at the University of Illinois.
All of the women in the study were mothers with depressive symptoms. They were classified into three categories by level of severity: mild or clinically insignificant depression; moderate depression; and severe depression, such as suicidal thoughts, panic and frequent crying.
The researchers found that two-thirds of women who experienced the severest symptoms reported that the onset occurred during pregnancy, while symptoms in women with moderate depression typically began postpartum.
Further, the severely depressed women were more likely than the moderately depressed group to experience complications during delivery, whereas the moderately depressed group was more likely to have problems during pregnancy, such as pre-eclampsia, gestational diabetes and hypertension.
The findings could mean that different biological factors influence women who experience depression during pregnancy than those who develop it after birth, which is believed to be connected to falling hormone levels after delivery.
In addition, Samantha Meltzer-Brody, the study's corresponding author and director of the perinatal psychiatry program at the University of North Carolina, said she is interested in whether immune system issues might play a role, given that 60% of the moderately depressed women reported conditions such as diabetes.
Building off of the study, Meltzer-Brody and colleagues will collect DNA from thousands of women through an online registry, which could eventually help "determine who's at risk," she said (Belluck, "Well," New York Times, 2/2).