Postpartum depression has devastating consequences for new moms and their families. The stress of childbirth combined with changing hormone levels can contribute to feelings of sadness and anxiety (a condition known as "the baby blues") as well as more serious depressive episodes. In the current issue of the journal Neuron, researchers from the University of California at Los Angeles present research on a neural mechanism that may be involved in postpartum depression, and their work could lead the way toward new avenues of treatment.

The study focused on GABA, an inhibitory neurotransmitter that helps regulate neural activity and that is associated with hormonal fluctuations. GABA levels diminish during pregnancy as hormones rise, and when hormones return to their normal levels after childbirth, GABA increases. The researchers developed an accurate mouse model of postpartum depression by breeding mice to lack a particular component of GABA receptors, the delta subunit. In these mice, GABA receptors were unable to adapt in response to changing hormone levels.

By comparing pregnant mice and mice that had recently given birth to mice that had never been pregnant, the researchers demonstrated the association between impaired functioning of GABA receptors and symptoms of depression and anxiety following pregnancy. Mice that had recently given birth and that also had impaired GABA receptors became less active than other mice and did not seek out pleasure. Additionally, they engaged in abnormal behaviors that endangered the health of their pups, such as failing to build nests for the babies. By giving these mice a drug that acts on receptor activity, the researchers were able to restore GABA functioning and saw the mice abandon their maladaptive behaviors, which allowed for a higher rate of survival among the young mice.
 
Postpartum depression disrupts the lives of an estimated 15 percent of new moms, and continued research, especially in human subjects, is necessary to more clearly understand this disorder. The current study has indicated a potential treatment strategy, and with further research, we may be better able to aid women during a time when they could be particularly vulnerable to depression. Early treatment can be a vital aspect of recovery, allowing women to take control of their symptoms early on, improve their physical and mental well-being, and ensure the healthy development of their children.