DSM-V: modifying the postpartum-onset specifier to include hypomania.

By failing to include it under the rubric of the postpartum-onset specifier, Diagnostic and Statistical Manual of Mental Disorders (DSM)-IV-TR has ignored the clinical reality that childbirth is a potent trigger of hypomania. Given the serious and occasionally tragic consequences of misdiagnosis of bipolar II depression as unipolar depression in the postpartum period, it is argued that DSM-V should consider modifying the postpartum-onset specifier to include episodes of hypomania.