Wonder Woman Nursing, Paolo Borile, Italy
Six months of nursing on lamotrigine or levetiracetam caused no harm by age 6, and may have helped
STUDY: Li Y et al, JAMA Netw Open 2026
STUDY TYPE: Prospective cohort study
FUNDING: National Institute of Neurological Disorders and Stroke; Eunice Kennedy Shriver National Institute of Child Health and Human Development
Background
Breast milk has health benefits that formula does not replace, raising the possibility that it may benefit the baby more to breastfeed while on a medication than to formula feed to avoid exposure to a medication. That was the case with valproate. Children who breastfeed while their mothers took valproate grew up to have higher IQs at age 6 than those who were formula fed.
That’s a remarkable finding, considering valproate has serious toxicity during fetal development. This study looks at long term outcomes after exposure to lamotrigine and levetiracetam in breast milk.
The Study
- 273 children of women with epilepsy taking anticonvulsant medications and 84 children of healthy women, enrolled during pregnancy at 20 US epilepsy centers.
- Most mothers took lamotrigine or levetiracetam; about a quarter used multiple medications.
- Breastfeeding was grouped as none, under 6 months, or 6 months or longer.
- Blinded raters measured verbal language and adaptive behavior (ABAS-3, a parent-rated scale of daily living, social, and thinking skills) at age 6.
Results
There was a possible advantage to breastfeeding even while on the medication.Among children of mothers with epilepsy, nursing for 6 months or longer raised adaptive behavior scores about 5 points over no breastfeeding, mainly in practical and conceptual skills.
When comparing breastfed children of mothers on anticonvulsants to those from healthy mothers, there were no significant differences, suggesting safety of the medication. The two groups scored nearly the same on language, adaptive behavior, nonverbal ability, overall cognition, and autism risk.
The gain was largest with monotherapy, particularly lamotrigine (about 6 points pooled). Polytherapy showed no benefit, but no harm either.
Limitations
Observational (not randomized), imperfectly controlled.
Practice Implications
- These mothers had epilepsy, but the findings apply to bipolar disorder.
- Lamotrigine and levetiracetam are safer than previously thought in breastfeeding, and breastfeeding itself has benefits over formula feeding.
- Lamotrigine passes into the breastmilk, and breastfed infants have levels that are about 30% that of the mother.
- There is a theoretical risk of allergic rash in infants exposed to lamotrigine for the first time through breast milk, but there are not case reports of this, and it is unlikely to happen if there was exposure during pregnancy.
—Chris Aiken, MD
Director, Psych Partners
Editor in Chief, Carlat Psychiatry Report
