Mood episodes in pregnancy and risk of postpartum recurrence in bipolar disorder: The Bipolar Disorder Research Network Pregnancy Study

Background
Women with bipolar disorder (BD) are at high risk of mania/psychosis following childbirth. The risk factors for these episodes remain poorly understood and prospective studies are rare. Here, we examine whether mood episodes occurring within pregnancy predict postpartum recurrence in women with BD using a prospective design.

Method
128 women with DSM-5 BD were followed from week 12 of pregnancy (baseline) to 12-weeks postpartum. Semi-structured interviews, supplemented by clinician questionnaires and case-note review, assessed lifetime psychiatric history at baseline, and perinatal psychopathology at two follow-up assessments: third-trimester of pregnancy and 12-weeks postpartum.

Results
Postpartum follow-up data were obtained for 124/128 (97%) women [98 bipolar I disorder/schizoaffective-BD (BD-I/SA-BD group) and 26 bipolar II disorder/other specified BD and related disorder (BD-II/BD-OS group)]. Perinatal recurrence was high in both diagnostic groups (57% and 62% respectively). Women with BD-I/SA-BD were significantly more likely to experience mania/psychosis within 6 weeks postpartum (23%, n=22/96) compared to those with BD-II/BD-NOS (4%, n=1/25; p=0.042). In BD-I/SA-BD, mania/psychosis in pregnancy significantly elevated risk of mania/psychosis postpartum compared to remaining well (RR 7.0, p<0.001) and experiencing non-psychotic depression in pregnancy (RR 3.18, p=0.023)

Limitations
Predominantly United Kingdom White sample and limited BD-II/BD-OS sample size.

Conclusions
Women with BD are at high risk of recurrence during pregnancy and the postpartum. Over and above risk conferred by a history of BD-I/SA-BD, mania/psychosis during pregnancy further increased risk of postpartum mania/psychosis in this high-risk group. These data may have important implications for prediction and management of severe postpartum recurrence of BD.