Women with bipolar disorder have a high risk for symptom exacerbation during pregnancy and the risk is elevated further when mood stabilizers are discontinued. This report describes a 31-year-old bipolar woman who discontinued medication before pregnancy but had to resume her pharmacotherapy due to manic episodes that recurred during the second trimester. Olanzapine, an atypical antipsychotic, was administered from week 25 of gestation and then replaced with quetiapine in week 35 of gestation. Even though a consensus on clinical interventions for pregnant patients with symptom relapse has not been reached, clinicians should still discuss pregnancy and therapeutic management with every female bipolar patient of childbearing age. This discussion is important because treatment can be managed most effectively in these individuals if pregnancy is planned. Ultimately, clinical decisions should be made on a case-by-case basis, weighing the risks to the mother and fetus between the disorder itself and the teratogenicity of pharmacotherapy.