Relationship of Toxoplasmosis during Pregnancy with the Results of the Newborn Hearing Screening
Introduction: Hearing is a complex function and its integrity is essential for the acquisition and development of language. An infection by Toxoplasma gondii during pregnancy can damage the auditory system of the neonate.
Objective: To compare the results of neonatal hearing screening of newborns of mothers diagnosed positive for toxoplasmosis infection with the results of newborns of mothers with a negative diagnosis.
Methods: A prospective cohort study was performed in the neonatal hearing screening program in Dr. Ary Pinheiro Base Hospital in Porto Velho, Rondônia. Twenty-nine newborns of mothers who had tested positive for toxoplasmosis in pregnancy (exposed group) and 89 newborns born from mothers with negative test (unexposed group) matched for gestational age, birth weight, and the occurrence of risk factors for hearing. All underwent hearing screening by electrophysiological measures. The variables were collected in the mothers’ and newborns’ medical records.
Results: There was no significant difference between groups regarding gestational age, birth weight, and risk indicators for hearing. We observed a significant number of failure in the exposed group (13.8%) compared with the unexposed group (2.2%). The relative risk for the exposed group fails the hearing screening with transient evoked otoacoustic emissions is 9.21 and 7.41 when combined with automated auditory brainstem response.
Conclusion: Newborns of mothers diagnosed positive for toxoplasmosis during pregnancy have a higher risk of failing in the hearing screening, regardless of methodology.
Keywords: Newborns, neonatal screening, hearing loss, toxoplasmosis, pregnancy.