By PAM BELLUCK
FEBRUARY 2, 2015 6:05 PM
A large new study has documented unexpected links in the timing and severity of symptoms of maternal depression, which could help mothers and doctors better anticipate and treat the condition.
The study of more than 8,200 women from 19 centers in seven countries, published last month in Lancet Psychiatry, found that in those with the severest symptoms — suicidal thoughts, panic, frequent crying — depression most often began during pregnancy, not after giving birth, as is often assumed.
Moderately depressed women often developed their symptoms postpartum, and were more likely than severely depressed women to have experienced complications during pregnancy like pre-eclampsia, gestational diabetes or hypertension.
Severely depressed women, however, more often reported complications during delivery.
“This is the largest study to date on postpartum depressive symptoms,” said Leah Rubin, an assistant professor in the Women’s Mental Health Research Program at University of Illinois at Chicago, a co-author of a commentary about the study. “This is definitely a first step in the right direction, knowing that depression isn’t one-size-fits-all.”
Ten to 20 percent of mothers experience depression, anxiety, bipolar disorder or other symptoms at some point from pregnancy to a year after giving birth. The study could aid efforts to find causes and treatments.
The study participants were all mothers. Some had been found to have postpartum depression by clinicians, while others were assessed via a widely used questionnaire. (Some participants fell into both groups.)
Each group could be separated into three subgroups representing women with severe, moderate, and either mild or clinically insignificant depression, said Dr. Samantha Meltzer-Brody, the director of University of North Carolina’s perinatal psychiatry program and the study’s corresponding author.
Dr. Meltzer-Brody said the finding that two-thirds of severe depression began during pregnancy raised scientific questions. The biological factors at work could differ from those affecting women with classic postpartum depression, which scientists think may be linked to plummeting hormone levels after delivery.
She also wondered whether the finding that 60 percent of moderately depressed women reported issues like diabetes suggested that immune system problems might underlie their symptoms.
Dr. Meltzer-Brody and her colleagues will begin seeking answers this year by collecting DNA from thousands of women through an international online registry.
“Ideally, you could determine who’s at risk,” she said. “What we do now is wait for people to get sick.”