Lithium Side Effects May Increase Risk Of Birth Defects: Study

New research suggests that the use lithium during pregnancy could increase the risk of children suffering certain types of birth defects. 

In a study published last week in the medical journal The Lancet Psychiatry, researchers from Denmark warn that they saw a significantly increased risk of major malformations among children whose mothers took lithium during the first trimester of pregnancy, indicating that doctors should weigh these risks when prescribing lithium to combat mood disorders in pregnant women.

Lithium-based medications, such as Lithane or Lithobid, are often used to treat manic episodes of bipolar disorder, and other forms of mania. The drug has been on the market for about half a century, and about three percent of the U.S. population have bipolar disorder.

Researchers conducted a meta-analysis of data on pregnant women and their children collected from Denmark, Sweden, Canada, the Netherlands, the U.K. and the U.S. from 1997 to 2015. The study looked for lithium exposure, mood disorders, pregnancy complications, delivery outcomes, neonatal readmission to the hospital within 28 days of birth and congenital malformations.

More than 22,000 pregnancies were identified as eligible, with 727 involving lithium exposure.

According to the findings, there was a 71% increased risk of major malformations among the children of women who took lithium during the first trimester of pregnancy. The findings also indicated a 62% increased risk of neonatal readmission within 28 days of birth. They did not find any risk linked to complications or delivery outcomes, however.

Researchers also said that they did not find a significant increased risk of major heart malformations, which contradicts the findings of Harvard researchers published almost exactly a year ago. That study found that the overall risk of cardiac malformations was 65% higher in infants whose mothers took lithium during the first trimester.

“Considering both the effect sizes and the precision of the estimates in this meta-analysis, treatment decisions for pregnant women with mood disorders must weigh the potential for increased risks of lithium during pregnancy – in particular those asociated with use of lithium during the first trimester – against its effectiveness at reducing relapse,” the Danish researchers concluded.