POSTPARTUM DEPRESSION
The immune system offers clues
For decades scientists have been trying to solve the mystery of postpartum depression, including why it strikes some women and not others. The illness – marked by intense feelings of sadness and even thoughts of harming a child or oneself – can be devastating to mothers, newborns and entire families.
Now, emerging research may hold answers. Although postpartum depression has commonly been linked to the hormonal fluctuations of pregnancy, scientists say that the immune system may play a much larger role than previously known.
The findings have the potential to profoundly change how doctors diagnose and treat pregnancyrelated depression. Most important, the research could one day identify mothers most at risk, so that support and treatment could begin before symptoms occur.
The focus on the link between immune health and postpartum depression is part of a seismic change happening in the study of psychiatric illnesses. Scientists around the world are finding that underlying autoimmune and inflammatory processes can have a profound impact on the brain and may be more common than previously believed in patients with a variety of neuropsychiatric conditions, including major depression.
Scientists have found that motherhood causes such dramatic remodeling of the brain that many researchers now consider it to be “like another critical period of brain development, like early life or adolescence,” said Benedetta Leuner, associate professor of psychology at Ohio State University.
These brain changes may be a key to understanding both nurturing maternal behavior and how pregnancy-related depression can develop. And many experts believe that increasing awareness of the biological mechanisms of postpartum depression can help combat the all-too-commonplace stigma and shame that often accompany it.
THE BIOLOGICAL TOLL OF PREGNANCY-RELATED DEPRESSION
Many mothers experience the “baby blues,” a period of sadness, irritability and crying spells that typically lasts a few days following childbirth. But an estimated 1 in 5 women – about 700,000 Americans a year – experience a more severe, prolonged and debilitating depression during or after pregnancy, marked by intense feelings of hopelessness, disinterest and, in rare cases, psychosis. (Scientists prefer the term “peripartum depression” or PPD because about a third of the cases begin during pregnancy.)
The feelings can persist for weeks, months or even years, and can hamper parent-infant bonding and caretaking. It is also a leading cause of preventable maternal mortality: Suicide accounts for 20 percent of postpartum deaths.
Earlier this year, the Food and Drug Administration for the first time approved a pill to specifically treat the condition. The drug, sold under the brand name Zurzuvae, is a neuroactive steroid that mimics a natural metabolite of the hormone progesterone.
The drug is widely viewed as a game changer in helping women cope, but it doesn’t solve the problem of identifying those at highest risk of PPD. Nor is it, along with standard therapy and antidepressants, expected to work on every woman.
“We do not know how to treat it as well as we should,” said Tsachi Ein-Dor, an associate professor of psychology at Reichman University in Israel.
AN IMMUNE RESPONSE TO PREGNANCY AND PARENTHOOD
Increasingly, scientists are finding that shifting hormones are not the whole picture in PPD. The immune system also fluctuates in its activity during pregnancy.
“Immune changes are one of the most important changes that have to occur in order to essentially, you know, tolerate a visitor in your body for nine months,” said Kathryn