Question: Despite some warnings to the contrary, lithium is often used a treatment for bipolar disorder in females of child bearing age. During the first trimester of pregnancy, maternal use of lithium is associated with an increased risk in which category of fetal malformations?
Answer: Maternal use of lithium is associated with an increased risk of cardiac malformations, including Ebstein’s anomaly. However, the cited study of more than 1,300,000 pregnancies reported approximately “1 additional case [of cardiac malformations] per 100 live births when there was exposure early in pregnancy and that this association is dose dependent. (Patorno E et al. Lithium use in pregnancy and the risk of cardiac malformations. 2017 NEJM 376(23):2245-2254)