It is estimated that 2 to 5 percent of dads are afflicted with postpartum depression. Photo by Sara Brennen

Celebrity moms Gwyneth Paltrow, Marie Osmond and Brooke Shields have all opened up publicly about their battles with postpartum depression, or PPD. As their stories make clear, while bringing a new baby home is thought of as one of life’s happiest times, some women struggle with symptoms of clinical depression -- including sadness, anxiety and irritability -- after delivering a baby. Combined with the fatigue of parenting an infant, PPD can be a serious problem for moms -- but what about the dads? Can men experience postpartum depression, too?

Paternal is well known to researchers, said Douglas Teti, Penn State professor of human development, psychology and pediatrics. Although awareness is low in the general public and the medical community, we shouldn't be surprised that dads can get the baby blues "The transition to parenthood is stressful for men as well as for women," he said.

More is known about postpartum depression in mothers than in fathers, but current estimates suggest that 2 to 5 percent of dads and 12 to 20 percent of moms are affected. In women, hormonal fluctuations associated with pregnancy and birth are often blamed for mood changes, but Teti said that in either parent, personal history has a strong influence on depression.

"In women, it's very common for postpartum depression to be linked to earlier episodes of depression. The same association applies to men," Teti said. Parents also affect each other. Having one parent with postpartum depression is a strong predictor of depression in the other parent.

It's important to remember that PPD is more than just manageable stress, Teti said.

"Some stress is normal and expected. Depression is when the stress becomes debilitating, and starts to affect emotion and cognition in a negative way." Parents should get help, both for themselves and their kids, he said.

Studies suggest that postpartum depression in moms or dads could have long-term consequences for their children. One of Teti's current studies investigates how infant sleep affects child development. This includes looking at parenting behavior at bedtime, and how parental depression might affect infant sleep quality. Clearly, postpartum depression is a family issue, said Teti.

"It's not just a problem that affects one person. If a mother comes in with depression, one of the first things we should ask is 'how is the father coping?'" People shouldn’t be ashamed of PPD, he said, but should reach out for help as soon as possible. "It's treatable. A combination of antidepressant medicine and therapy is often the best course of action."