From the Guidelines
Lithium use during pregnancy is associated with potential risks to the fetus, and its use should be carefully considered and monitored by a psychiatrist and obstetrician. The medication has a black box warning stating that lithium toxicity is closely related to serum lithium concentrations and can occur at doses close to therapeutic concentrations, and based on animal studies, lithium may cause fetal harm 1. Human studies suggest fetal harm but are insufficient to determine risk.
When considering lithium use in pregnancy, it is essential to weigh the potential benefits against the risks. Women with severe bipolar disorder may require continued treatment with lithium despite the potential risks to the fetus, as the risks of untreated illness can be significant 1. However, regular monitoring of lithium levels is crucial during pregnancy, as physiological changes can necessitate dose adjustments.
Some key considerations for lithium use during pregnancy include:
- Regular monitoring of lithium levels, typically monthly during pregnancy and weekly near delivery 1
- Fetal echocardiography is recommended at 16-20 weeks gestation to assess for potential cardiac malformations
- The dose may need to be reduced just before delivery and increased postpartum to minimize the risk of neonatal complications
- Women should be aware of the potential risks of lithium use during pregnancy, including cardiac malformations, neonatal complications, and lithium toxicity in the newborn 1
It is crucial for women with bipolar disorder who are pregnant or planning pregnancy to consult with both a psychiatrist and obstetrician to develop a personalized treatment plan that balances the risks and benefits of lithium use 1.
From the FDA Drug Label
WARNINGS Lithium may cause fetal harm when administered to a pregnant woman. There have been reports of lithium having adverse effects on nidations in rats, embryo viability in mice, and metabolism in-vitro of rat testis and human spermatozoa have been attributed to lithium, as have teratogenicity in submammalian species and cleft palates in mice Studies in rats, rabbits and monkeys have shown no evidence of lithium-induced teratology. Data from lithium birth registries suggest an increase in cardiac and other anomalies, especially Ebstein’s anomaly. If the patient becomes pregnant while taking lithium, she should be apprised of the potential risk to the fetus If possible, lithium should be withdrawn for at least the first trimester unless it is determined that this would seriously endanger the mother. Pregnancy Teratogenic Effects - Pregnancy Category D: See WARNINGS section
Lithium use in pregnancy is associated with potential fetal harm, including increased risk of cardiac anomalies and Ebstein's anomaly. The FDA recommends that lithium be withdrawn for at least the first trimester unless it would seriously endanger the mother 2. Lithium is classified as Pregnancy Category D, indicating that there is positive evidence of human fetal risk based on adverse reaction data from investigational or marketing experience or studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks 2.
- Key considerations:
- Lithium may cause fetal harm
- Increased risk of cardiac anomalies and Ebstein's anomaly
- Withdrawal of lithium for at least the first trimester is recommended unless it would seriously endanger the mother
- Lithium is classified as Pregnancy Category D
From the Research
Risks Associated with Lithium Use in Pregnancy
- Lithium use during pregnancy has been associated with an increased risk of congenital malformations, particularly cardiac malformations 3
- The risk of cardiac malformations is higher with lithium exposure during the first trimester, with an adjusted risk ratio of 1.65 compared to unexposed infants 3
- The risk of Ebstein's anomaly, a specific type of cardiac malformation, is also increased with lithium exposure, with an adjusted risk ratio of 2.66 3
- Other studies have confirmed the association between lithium exposure and congenital malformations, but with lower risk estimates than previously reported 4
Management of Lithium Use in Pregnancy
- Lithium levels should be monitored frequently during pregnancy, preferably weekly in the third trimester 4
- A high-resolution ultrasound with fetal anomaly scanning is recommended at 20 weeks 4
- Delivery should take place in a specialized hospital with psychiatric and obstetric care for the mother and neonatal evaluation and monitoring of the child 4
- Lithium can be restarted immediately after delivery as a strategy for relapse prevention postpartum 4
Breastfeeding and Lithium Use
- Most clinical guidelines discourage breastfeeding in women treated with lithium 4
- Mothers who choose to breastfeed should watch for signs of toxicity in their babies 5