乌鸦传媒

No increased risk of major fetal malformations or spontaneous abortion was seen in pregnancies exposed to oral or topical terbinafine, according to a nationwide cohort study in Denmark.

Among more than 1.5 pregnancies over a 20-year period, rates of major malformation were virtually identical whether they were exposed to oral (prevalence odds ratio 1.01, 95% CI 0.63-1.62) or topical terbinafine (prevalence OR 1.08, 95% CI, 0.81-1.44), relative to unexposed pregnancies, according to Niklas W. Andersson, MD, of Copenhagen University Hospital Bispebjerg and Frederiksberg, and colleagues.

Absolute risk differences were 0.04% and 0.26% with oral and topical terbinafine, according to the group's report in .

Spontaneous abortion rates didn't differ either. Rates were 10.4% of pregnancies exposed to oral terbinafine, compared to 10.3% of unexposed pregnancies (HR 1.06, 95% CI 0.86-1.32). In pregnancies exposed to topical terbinafine, spontaneous abortion occurred in 5.2% of pregnancies, compared to 5.1% in unexposed pregnancies (HR 1.04, 95% CI 0.88-1.21).

"This study provides the first data from routine clinical practice on the association between terbinafine use (in both oral and topical formulations) in pregnancy and risk of major malformations and spontaneous abortion," Andersson told 乌鸦传媒 in an email. Andersson added that these results may provide reassurance to pregnancies exposed to terbinafine, and inform clinical practice.

Terbinafine is a frequently used antifungal agent that is available as an oral or topical treatment, according to Andersson. It is used to treat many common skin and nail conditions, including dermatophyte infections like ringworm or onychomycosis.

Currently, the FDA recommends that terbinafine therapy should not be initiated during pregnancy, Andersson and colleagues wrote, but research on fetal risk is limited.

In an accompanying editorial, Mary Kathryn Abel, AB, and Jenny E. Murase, MD, of the University of California San Francisco, said that this study is the largest and most statistically rigorous research of this topic to date.

"In light of those data, the study by Andersson et al suggests that oral and topical terbinafine may be one of the safest, if not the safest, option to treat fungal infections in the pregnant population," Abel and Murase wrote.

Although Abel and Murase said that oral and topical terbinafine might be the safest option to treat fungal infections during pregnancy, they added that it does not mean it should be used. While reassuring, the current study doesn't settle all questions about the drug's safety in pregnancy or during lactation. Consequently, the editorialists recommended postponing its use for asymptomatic infections.

Data for the study came from a national registry of more than 1.5 million pregnancies in Denmark from 1997 to 2016. Terbinafine exposure was defined as at least one prescription fill for the drug in oral or topical form.

About 1 million pregnancies were included in the analysis for major malformations, and 1.4 million were included for spontaneous abortion. Just under 900 pregnancies were exposed to oral terbinafine, and around 3,100 were exposed to topical terbinafine. Around 40,000 unexposed pregnancies were included for a matched outcome analysis.

Andersson and colleagues noted limitations to their analysis, including potential confounding factors that were not measured, such as other drug use and body mass index. In addition, data were lacking on the indications for terbinafine therapy, which might have influenced risks of adverse pregnancy outcomes.

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