The increased risk of onset or recurrence of bipolar disorder during the perinatal period is a critical issue that needs to be carefully considered, particularly regarding the management of mood stabilizers. For clinicians, the prescription of mood stabilizers is challenging during pregnancy—as for any psychotropic drug—whether it is an existing treatment or a new one. Prescriber must always weigh the risk of maternal relapse in the event of discontinuation against the risk of antenatal foetal exposure to the drug. In other words, should treatment be modified, switched, or discontinued on the basis of the potential teratogenic and/or fetotoxic risk associated with antenatal exposure to the drug versus the risk of maternal relapse in the event of any modification? Current data and increasing knowledge suggest that conventional wisdom on lithium probably needs to be reconsidered, while the use of antiepileptics should probably be greatly moderated, except for lamotrigine.