A longitudinal study of hypomania and depression symptoms in pregnancy and the postpartum period

Childbirth is a potent precipitant of severe episodes of bipolar disorder. We investigate mood longitudinally through pregnancy and the postpartum period, using the Highs Scale and the Edinburgh Postnatal Depression Scale (EPDS), to examine if the postpartum period is a time of increased risk for hypomanic symptoms in the general population. A total of 446 women were recruited at 12 weeks of pregnancy from the Birmingham Women's Hospital and four midwife-led community clinics. Women completed the Highs Scale and the Edinburgh Postnatal Depression Scale at 12 weeks of pregnancy, one week postpartum, and eight weeks postpartum. Cases of probable depression, as defined by an EPDS score of 13 or greater, did not significantly increase from pregnancy to the postpartum period. The prevalence of 'the highs' was eightfold higher in the postpartum week than during pregnancy. Consistent with the increased rates of severe manic illness following childbirth, we find that more minor hypomanic states are also increased. We consider the clinical relevance of postpartum hypomanic symptoms and the implications of these findings for research into postpartum-onset mood symptoms.