As many as 9% of pregnancies are complicated by pre-existing or gestational
diabetes, and one in 10 new mothers struggles with postpartum depression.
The new findings suggest, but do not prove, that diabetes is a risk factor
for depression in this group, researchers say.
Pregnant women and new moms in the study had nearly twice the incidence of
depression as non-diabetic women who were pregnant or had just given birth.
The study included only low-income women, and it is not clear if the
findings extend to other groups of pregnant women and new moms.
Study researcher Katy Backes Kozhimannil, who is a doctoral candidate at
Harvard Medical School, tells WebMD that more research is needed to determine
if diabetes plays a direct role in depression during and immediately after
"This is a potential new risk factor for postpartum depression, and we
really don't have many of those," she says. "Diabetes and depression are both
treatable illnesses. If we are able to show that women with diabetes are more
vulnerable to postpartum depression we can target detection and intervention
efforts to this group."
The study included just over 11,000 low-income New Jersey women receiving
Medicaid who gave birth between July 2004 and September 2006.
Those with either pre-existing type 1 or type 2 diabetes or
gestational diabetes were significantly more likely to experience depression
during pregnancy or in the postpartum period.
After controlling for noneconomic risk factors for postpartum depression,
women with diabetes had nearly double the odds of having a diagnosis of
depression or taking antidepressant
medication in the months immediately following delivery, compared to women
About 10% of women with diabetes and no history of depression developed
postpartum depression, compared to 6% of nondiabetic women with similar
histories, Backes Kozhimannil says.
"These findings do not establish that diabetes is a cause of postpartum
depression, only that they are related to each other in some way," she says.
"There are certainly many unanswered questions, but this is the first study to
examine this relationship and we need to pay attention to these findings."
Hormonal Changes and Depression
The study is the first to link diabetes to postpartum depression. But an
increasing body of evidence links diabetes to depression in the general
In a study published last June, Sherita Hill Golden, MD and colleagues from
Johns Hopkins Medical School reported an increased incidence of depression in
middle-aged patients with type 2 diabetes.
Golden tells WebMD that she is not surprised by the findings in the newly
"Patients with diabetes have to do a lot of things, including monitoring
their glucose and modifying their diets," she says. "Some of these things can
be perceived as burdens and could increase the risk for depression, especially
in a very vulnerable population like pregnant women."
It has also been suggested that hormonal changes that occur with diabetes
could exacerbate the hormonal changes that accompany pregnancy, making this
group especially vulnerable to depression.
Golden says a better understanding of the relationship between diabetes and
depression in all groups could improve the treatment of both conditions.
"There is certainly a need for a heightened awareness about the risk for
depression in diabetic patients," she says.