Postpartum depression is often framed as a private struggle that unfolds at home or in the doctor’s office. But for millions of working parents, its effects also show up quietly at work—through missed deadlines, sudden disengagement, or a colleague who no longer seems like themselves. Too often, these changes are misunderstood as performance issues rather than signs of a common and treatable mental health condition.

To better understand what employers, managers, and coworkers often miss—and how workplaces can respond more thoughtfully—I spoke with Andrea Clark, deputy CEO of Postpartum Support International, a global nonprofit focused on supporting families and raising awareness about perinatal mental health disorders.…