The purpose of this study was to review the use of lithium in pregnancy and its effects on the neonate. This was a case study and review of the published literature. Lithium is commonly used in the treatment of psychiatric disorders, specifically bipolar depression. Bipolar disorders that require treatment with lithium demand special consideration when the woman becomes pregnant. Reported neonatal problems with maternal lithium therapy include Ebstein's anomaly, poor respiratory effort and cyanosis, rhythm disturbances, nephrogenic diabetes insipidus, thyroid dysfunction, hypoglycemia, hypotonia and lethargy, hyperbilirubinemia, and large-for-gestational-age infants. Lithium can have adverse effects on the fetus and newborn infant, but data suggest normal behavioral patterns in childhood.