Researchers have found that two hormones can modify the effects of maternal stress on a number of childhood behaviors, according to an article in Frontiers in Endocrinology. The study, which was performed in rats, suggests that treating a stressed mother with hormones might help alleviate anxiety, repetitive behaviors, and social deficits in her offspring.

The damaging effects of chronic stress in the development of depression and anxiety disorders are well documented. But the effects of stress on parents, especially the stress of postpartum depression and anxiety, can be even more far-reaching. Using an animal model of postpartum depression and anxiety, researchers have found that maternal stress affects behavior not only in children, but also in grandchildren.

In new work published online December 14, 2016, a team of scientists tested two different hormones as possible treatments to prevent the effects of maternal stress on offspring. The researchers, led by Benjamin Nephew, Ph.D., a 2014 NARSAD Young Investigator grantee at Tufts University Cummings School of Veterinary Medicine, focused on oxytocin and the closely-related hormone vasopressin. Oxytocin is already under investigation as a treatment for postpartum depression and anxiety, with preliminary results mixed.

The researchers used a chronic social stress-based rat model of postpartum depression and anxiety to evaluate the hormones. In the first generation, maternal female rats (mothers) and their pups were exposed to a “novel” male rat. This is stressful for the both the mother and her offspring, and depresses maternal care. When the female offspring (exposed to early-life social stress) became mothers themselves, their maternal care was also depressed, and their daughters (“grandchildren” of the original moms) exhibited anxiety, repetitive behaviors, and impaired social behavior.

The researchers next performed the same experiments, but this time administered either vasopressin or oxytocin to the “children” of stressed mothers.  This was done during lactation to see how the hormones might affect the “grandchildren” when they reached the juvenile stage. Both vasopressin and oxytocin reduced anxiety and repetitive behaviors and increased social behavior in female “grandchildren,” with behaviorally specific actions.

The new research suggests that maternal oxytocin and vasopressin may be effective at preventing the adverse behavioral effects of postpartum depression and anxiety on children.  Ongoing research in rodents is investigating the effects of these hormones on maternal behavior in children of stressed mothers.