Women who take antidepressants when they’re pregnant could unknowingly predispose their kids to type 2 diabetes and obesity later on in life, new research out of McMaster University suggests.

The study, conducted by associate professor of obstetrics and gynecology Alison Holloway and PhD student Nicole De Long, found a link between the antidepressant fluoxetine and increased risk of obesity and diabetes in children.

Holloway cautions that this is not a warning for all pregnant women to stop taking antidepressants, but rather to start a conversation about prenatal care and what works best on an individual basis.

“There are a lot of women who really need antidepressants to treat depression. This is what they need,” Holloway told CBC. “We’re not saying you should necessarily take patients off antidepressants because of this — but women should have this discussion with their caregiver.”

“Obesity and Type 2 diabetes in children is on the rise and there is the argument that it is related to lifestyle and availability of high calorie foods and reduced physical activity, but our study has found that maternal antidepressant use may also be a contributing factor to the obesity and diabetes epidemic.”

Obesity, diabetes rates rising

According to a study out of Memorial University in St. John's, obesity rates in Canada have tripled between 1985 and 2011. Canada also ranks poorly when it comes to its overall number of cases of diabetes, according to international report from the Organization for Economic Co-operation and Development, released last year.

Seven per cent of Canadian of women are prescribed antidepressants during pregnancy, according to statistics provided by McMaster University. It’s even higher in the U.S. at 20 per cent. “That translates to a staggering number of women,” Holloway said.

Previous studies have found that pregnant women are particularly vulnerable to depression, and it’s estimated that up to one in five pregnant women experience symptoms of depression during pregnancy.

The McMaster study — which was conducted on rats, and not in human trials — found increased levels of fat in the infant’s liver as well as low grade inflammation of the liver. That contributes to a “pre-diabetic” state, and it also is associated with obesity, Holloway says.

Finding safe interventions

“We have demonstrated for the first time in an animal model that maternal use of a class of antidepressants called selective serotonin reuptake inhibitors, or SSRIs, resulted in increased fat accumulation and inflammation in the liver of the adult offspring, raising new concerns about the long-term metabolic complications in children born to women who take SSRI antidepressants during pregnancy,” PhD student Nicole De Long said.

If researchers can figure out why this is happening at the molecular level, they could also work to develop some “safe interventions” that could prevent damage to the baby — that could include “dietary interventions” or vitamin support, Holloway says.

The next stage of the research at McMaster will be to understand the pathways behind why these drugs pose a risk. “If we can understand how the antidepressant causes adverse metabolic outcomes in the offspring than we can design therapeutic strategies to prevent the damage while allowing women who require these drugs to be treated but reduce the potential harm to the offspring.”

“Really, we’ve just scratched the surface here.”