Although we tend to feel comfortable counseling patients to continue antidepres- sants during pregnancy, because most of them do not appear to cause congenital abnormalities, mood stabilizers are trickier. Lithium increases the risk of a rare cardiac defect, and both Depakote and Tegretol increase the risk of neural tube defects (see TCPR, April 2007). Thus, the majority of women elect to discontinue mood stabilizers when they become pregnant. This study attempted to determine the risk of a psychi- atric relapse when a mood stabilizer is dis- continued. Researchers enrolled 89 pregnant women with bipolar disorder (type I or II) who were taking mood stabilizers in a natu- ralistic, observational study in which they were assessed by a research psychiatrist each trimester and four times after birth. Most of these women were well-educated married Caucasians who worked outside the home. 62 of the 89 women (70%) chose to stop their mood stabilizers. These women were more than twice as likely to have a mood episode recurrence during pregnancy than women who continued their meds (85% relapse rate vs. 37%). Abrupt discon- tinuation was associated with much more rapid relapse (within an average of 2 weeks) than gradual discontinuation (22 weeks). Most of the recurrences were for depression or mixed states; only 6 out of the 89 patients had an episode of frank mania during the study (Viguera AC, et al., Am J Psychiatry 2007;164:1817-1824).

TCPR's Take: While it is clear that mood stabilizers protect against relapse, this finding in itself doesn’t make the risk/benefit judgment much easier for specific patients. The authors didn't report how severe these episodes were – clinically, this information is crucial, since patients can meet formal crite- ria for a mood episode and yet still have only mild to moderate symptoms, which can often be managed with psychotherapy, preventing the risks to the fetus associated with mood stabilizers.