Occurrence of postpartum manic or mixed episodes in women with bipolar I disorder: A systematic review and meta-analysis

Objective Accurate information on the frequency and prevalence of manic or mixed episodes is important for therapeutic, prognostic, and safety concerns. We aimed to estimate the risk of relapse of manic and mixed episodes after delivery in women with bipolar I disorder or schizoaffective disorder-bipolar type.Methods Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a comprehensive literature search in PubMed, PsycINFO, Embase, and Cochrane databases was carried out on November 17, 2022, using the terms ((bipolar disorder) OR (manic depressive illness)) AND (mania)) AND (postpartum)) AND (recurrence)) AND (relapse). The search was updated on March 29, 2023. Case studies and qualitative analyses were excluded. Twelve studies reporting on 3595 deliveries in 2183 women were included in the quantitative analysis.Results The overall pooled estimate of postpartum relapse risk was 39% (95% CI = 29, 49; Q(11) = 211.08, p < 0.001; I-2 = 96.31%). Among those who had a relapse, the pooled estimate of risk for manic and mixed episodes was 38% (95% CI = 28, 50; Q(11) = 101.17, p < 0.001; I-2 = 91.06%). Using data from the nine studies that reported the percentage of medication use during pregnancy, we estimated a meta-regression model with the percent medication use as a continuous explanatory variable. The estimated prevalence of relapse was 58.1% (95% CI, 9.6 to 39.3 to 76.8) for studies with no medication use and 25.9% (95% CI, 10.5-41.3) for studies with 100% medication use. The difference between the two prevalence estimates was statistically significant, z = -2.099, p = 0.0359.Conclusions Our findings suggest an overall pooled estimate of postpartum relapse risk of 39%, while the pooled estimate of risk for manic and mixed episodes was 38%. These findings highlight the need to educate patients with bipolar I disorder, and their healthcare professionals about the high risk of relapse of manic or mixed episodes after delivery.