WEDNESDAY, May 11, 2011 (Health.com) — Women who have lower levels of the brain chemical oxytocin toward the end of their pregnancy may be more prone to develop postpartum depression than expecting moms with higher levels, a new study suggests.
Known as the “love hormone” or “cuddle hormone,” oxytocin is released during human-to-human contact (such as breast-feeding) and is critical to mother-baby bonding. Previous studies have shown that women whose oxytocin levels rise during pregnancy are more attached to their babies, but this is the first study to suggest a link with postpartum depression, which affects roughly 1 in 5 women.
Researchers in Switzerland measured the amount of oxytocin in blood samples taken from pregnant women during their third trimester, and found that women with lower levels were more likely to report symptoms of depression within two weeks of giving birth.
The study was small, and more research will be needed to flesh out the relationship between oxytocin and postpartum mood. If the link is confirmed, however, oxytocin could provide a new way of identifying pregnant women who are at risk, so as to give them appropriate preventive care.
“It would be nice to know which women are more vulnerable,” says Alan Manevitz, MD, a clinical family psychiatrist at Lenox Hill Hospital, in New York City, who was not involved in the study. “We could watch them more thoughtfully.”
The researchers aren’t sure why low oxytocin levels might increase the risk of postpartum depression, but they have some guesses. For instance, the hormone is known to reduce stress and feelings of fear, which aren’t exactly uncommon in new parents.
“This may be of special relevance during the postpartum period, says the lead author of the study, Gunther Meinlschmidt, PhD, an assistant professor of psychology at the University of Basel. “During this time, the mothers are challenged by a bulk of potentially stressful—and in some cases fear-promoting—new conditions and demands.”
Moreover, animal studies suggest that low oxytocin levels may interfere with a mother’s feelings of closeness to her baby, which can contribute to postpartum depression, Meinlschmidt says.
Salih Yasin, MD, the chairman of ob-gyn at the University of Miami Miller School of Medicine, stresses that even if these theories are borne out, oxytocin is far from the only culprit that can influence a mother’s mood after birth.
“Postpartum depression has so many factors,” Yasin says. “Some of it has to do with socioeconomic status, the stress levels, the family history, previous depressive symptoms, the presence or absence of other medical conditions.”
Next page: Is it just the “baby blues”?