Objective: Sudden sensorineural hearing loss (SSNHL) is rare in pregnancy and can be attributed to pregnancy-induced changes in hormone levels that increase thrombogenic risk and alter cochlear microcirculation with consequent development of sudden deafness. The study aimed to analyze the risk factors associated with SSNHL in pregnant South Korean.
Methods: A retrospective study of the incidence and risk factors associated with SSNHL before pregnancy enrolled 401,470 Korean women who delivered between January 2010 and December 2014. All participants underwent a pre-pregnancy national health screening examination through the National Health Insurance Corporation. We investigated the risk factors in 459 pregnant women with sudden sensorineural hearing loss and in 401,011 pregnant women without SSNHL through the pre-pregnancy national health screening examination and adverse perinatal outcome.
Results: No statistically significant intergroup differences were observed in the maternal age, parity, method of delivery, gestational age at delivery, body mass index, blood pressure, as well as fasting blood glucose and cholesterol levels. After adjusting for maternal age, the pre-pregnancy body mass index was associated with an increased risk of sensorineural hearing loss in pregnancy (adjusted odds ratio 1.52, 95% confidence interval 1.04-2.22). The sensorineural hearing loss did not increase the risk for gestational hypertension, preterm birth (<37 weeks' gestation), small- and large-for-gestational-age infants, postpartum hemorrhage, placenta previa, and placental abruption.
Conclusion: SSNHL can occur throughout pregnancy and is associated with maternal pre-pregnancy obesity. Notably, it does not increase risks during delivery or cause adverse perinatal outcomes.
Keywords: Sudden sensorineural hearing loss; perinatal outcome; pregnancy.