Women with a history of bipolar disorder or postpartum psychosis are at extremely high risk of relapse postpartum. Although lithium prophylaxis has demonstrated efficacy in reducing postpartum relapse, the timing of prophylaxis remains controversial. Here we evaluate the use of lithium during pregnancy compared to initiation postpartum in women at high risk for postpartum psychosis.

In total, 76 pregnant women at high risk for postpartum psychosis were referred to our psychiatric outpatient clinic between 2003 and 2010. Women who were medication-free at the time of initial evaluation were advised to start lithium prophylaxis immediately postpartum. In contrast, women already on maintenance lithium during pregnancy were advised to continue this treatment.

All women with a history of psychosis limited to the postpartum period (PP, n = 30) remained stable throughout pregnancy despite being medication-free. In contrast, 23.9% of women with a history of bipolar disorder (BD, n = 46) relapsed during pregnancy, despite the majority using prophylaxis throughout pregnancy. Postpartum relapse was highest in women with BD who experienced mood episodes during pregnancy (63.6%). Remarkably however, none of the 21 women with PP using postpartum prophylaxis relapsed, compared to 44.4% of PP patients who declined lithium prophylaxis.

We recommend initiating prophylactic treatment immediately postpartum in women with a history of psychosis limited to the postpartum period, offering an important clinical advantage by avoiding in utero fetal exposure to prophylactic medication. Additionally, patients with BD require continuous prophylaxis throughout pregnancy and the postpartum period to effectively reduce their peripartum relapse risk.