Moreover, male postpartum depression may have more negative effects on some aspects of a child's development than its female counterpart, says James F. Paulson, PhD, of the Center for Pediatric Research at the Eastern Virginia Medical School in Norfolk, Va.
Paulson and colleagues reviewed data on more than 5,000 two-parent families with children aged 9 months.
That's a "striking increase" from the 3% to 5% of men in the general population that have depression, Paulson tells WebMD.
The research, presented here at the annual meeting of the American Psychiatric Association (APA), also showed that the 14% of new moms have postpartum depression. That compares to 7% to 10% of women in the general population.
Depressed Parents Less Likely to Read to Their Kids
The researchers looked to see whether the parents' depression affected their interaction with their children.
"What we found," Paulson says, "is that both moms and dads who were depressed were significantly less likely to engage in interactions such as reading, telling stories, and singing songs to their infants."
But only the dads' behavior significantly affected their child's development at 24 months -- "specifically in terms of how many words the child used," Paulson says.
"If their dads were depressed and didn't read to them, the infants had a much smaller vocabulary," he says.
There was no link between the baby-mom interactions and the child's command of words at 2 years.
Not Just Baby Blues
Postpartum depression isn't just the "baby blues." It's severe depression marked by feelings of sadness or emptiness, withdrawal from family and friends, a strong sense of failure, and even thoughts of suicide.
These emotions can begin two or three weeks after birth and can last up to a year or longer if untreated.