Mom's Lithium Use May Harm the Baby

NEW YORK (Reuters Health) - Fetal exposure to high concentrations of the mood-stabilizer lithium may be harmful to the fetus, possibly contributing to low Apgar scores -- a test used to evaluate babies shortly after birth -- and neuromuscular complications, according to a study.

Although lithium has been used during pregnancy for more than 40 years, information on its perinatal effects is limited, Dr. Jeffrey Newport of Emory University in Atlanta and colleagues explain in the American Journal of Psychiatry.

To investigate further, the researchers prospectively evaluated 10 pregnant women who were undergoing lithium therapy for bipolar disorder. In keeping with empirical guidelines, therapy was suspended within 1 to 2 days of scheduled delivery. They also reviewed the literature and identified 32 cases in which maternal lithium was administered throughout delivery.

Newport and his team found that higher lithium concentrations at delivery were associated with more complications in offspring.

For example, Apgar scores were significantly lower, hospital stays longer and rates of central nervous system and neuromuscular complications higher in infants with high lithium levels. In fact, say the investigators, the rate of all complications except that of gestational diabetes was consistently higher in this group.

Given these findings, the researchers urge the development of guidelines limiting lithium dosage and advocating temporary suspension before delivery to reduce neonatal lithium concentrations and hopefully avoid toxic levels of lithium during gestation.

SOURCE: American Journal of Psychiatry, November 2005.