Is gentamicin ototoxic to the fetus?

Area of Science:

• Obstetrics and Gynecology
• Neonatal Medicine
• Pharmacology

Background:

• Gentamicin is used during pregnancy for serious maternal and fetal infections.
• Concerns exist regarding potential fetal hearing loss due to gentamicin exposure in utero, prompting manufacturer warnings.
• Limited documented cases suggest a questionable link between gentamicin and congenital deafness.

Purpose of the Study:

• To determine if in utero exposure to intravenous gentamicin leads to audiologic deficits in infants.
• To analyze gentamicin usage patterns (indication, dosage, duration) and serum level monitoring.
• To assess confounding factors that could impact infant hearing.

Main Methods:

• Retrospective chart review of women who received gentamicin during pregnancy.
• Identification and review of audiology test results for exposed infants.
• Analysis of confounding factors for fetal deafness and infant hearing outcomes.

Main Results:

• No cases of hearing loss were documented in 40 live births exposed to gentamicin in utero.
• Pyelonephritis and chorioamnionitis were primary indications for gentamicin use.
• Maternal serum gentamicin levels were monitored, with no trough levels exceeding 2 mg/L; most infants passed hearing tests.

Conclusions:

• In utero gentamicin exposure did not correlate with an increased incidence of audiologic impairment in the studied infant cohort.
• The findings challenge previous concerns about gentamicin-induced congenital deafness.
• Further research may be warranted to fully elucidate the safety profile of gentamicin in pregnancy.