Carelon Research impact study: Topiramate use in pregnancy and the birth prevalence of oral clefts

August 2021 | Written by Daniel C. Beachler, PhD, MHS and Stephan Lanes, PhD, MPH

In celebration of the 25th anniversary of Carelon Research Founder’s Day, we’re rolling out a series of articles highlighting some of our most impactful work. These ‘impact studies’ have contributed to the growing evidence base that influences healthcare decision makers and healthcare policy and practice. They also showcase the diverse service offerings at Carelon Research. Though all our work aims to improve the quality of healthcare, we’re especially proud of this work from research teams across our organization.

Topiramate exposure is associated with an elevated birth prevalence of oral cleft lip and/or cleft palate, conditions affecting one in 1,000 babies born in the United States (Cleveland Clinic ).

According to the Centers for Disease Control and Prevention (CDC ), about one in every 2,800 babies born in the United States has cleft lip and one in every 1,700 babies is born with cleft palate. Children with this condition often have problems with feeding and speaking clearly and can have ear infections. They also might have problems with hearing and with their teeth.

Though multiple factors can increase the chance of having a baby with an orofacial cleft, a collaborative study by Carelon Research (formerly HealthCore) and our research partners, published in 2014 , found that first trimester exposure to topiramate, a medication used for the treatment of epilepsy, is associated with an increased prevalence of oral clefts.

The Safety and Epidemiology Research team at Carelon Research collaborated with research partners to conduct a retrospective cohort study using automated data from four sources from 1997 to 2011. By linking maternal records with child records, they ascertained the prevalence of oral clefts and compared the prevalence in infants of women exposed to topiramate in the first trimester (TPM cohort), infants of women formerly exposed to TPM or other antiepileptic drugs (FE cohort), and infants of women not exposed to TPM with similar medical profiles to the TPM cohort (SMP cohort).

Researchers found the birth prevalence of oral clefts was 0.36% (7/1945) in the TPM cohort, 0.14% (20/13 512) in the FE cohort, and 0.07% (9/13 614) in the SMP cohort. After adjusting for multiple factors, the increased prevalence of oral clefts remained two- to five-fold higher for TPM use in the first trimester than for each comparator group.

This research, along with other studies, supports the U.S. Food and Drug Administration’s warning in Topamax's package insert  for fetal toxicity which notes that “use during pregnancy can cause cleft lip and/or palate”.

Historically, pregnant women are not included in clinical trials submitted for approval of new medications. Regulators, therefore, rely on real-world data to identify potential risks. Fetuses may be susceptible to congenital effects at particular times of development.

Researchers are able to link exposures during critical periods of pregnancy to subsequent congenital anomalies, even those that are not apparent at birth but diagnosed early in childhood. By studying the effects of medications on pregnancy outcomes, Carelon Research is contributing crucial evidence about the safe use of medications for pregnant women to support informed medical decisions.

For more information about our safety & epidemiology capabilities, including pregnancy outcome studies, single and multi-database post-authorization safety studies, risk evaluation and mitigation (REMS), validation studies and machine learning, medical record review and abstraction, and survey based research, visit our safety & epidemiology services page.

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