IntroductionThe potential adverse effects of prolonged exposure to anesthetics in pediatric patients with severe‐to‐profound sensorineural hearing loss remain unclear. This study aimed to examine whether early bilateral cochlear implantation involving long‐duration anesthetic exposure caused greater developmental impairment than that with unilateral cochlear implantation.MethodsThis prospective observational study included normally developing infants with bilateral severe‐to‐profound sensorineural hearing loss aged 6 months to 2 years who were candidates for unilateral/bilateral cochlear implantation surgery. Baseline (T0), 6‐month (T1), and 1‐year (T2) Gesell Scale scores were measured. The outcomes included fine motor, adaptability, gross motor, language, and social skills scale 6 and 12 months postoperatively.ResultThe 90 enrolled children with bilateral severe‐to‐profound sensorineural hearing loss (unilateral n = 43; bilateral n = 47) had a younger bilateral group (11.00 ± 3.66 vs. 15.63 ± 6.99 months, p < .001). Anesthesia duration was longer in the bilateral group (271.57 ± 36.09 vs. 148.81 ± 25.60 min, p < .001). Gross motor, fine motor, adaptability, and language scores improved in both groups, and no significant between‐group differences occurred in the fine motor scale at T1 and T2. Language developmental quotients improved significantly in the bilateral group compared with the unilateral group at T1 (mean differences: 25.07 ± 4.37 vs. 10.88 ± 4.61, p < .001) and T2 (mean differences: 34.98 ± 5.94 vs. 15.28 ± 6.55, p < .001). Stepwise regression revealed that gross motor, adaptability, language, and social skill developmental quotients at T1 were positively correlated with those at T0. Gross motor, fine motor, and social skill developmental quotients at T2 were negatively correlated with age at operation. Language developmental quotients were positively correlated with T0 values (p < .001) and in the bilateral group (p < .001) at T1 and T2.ConclusionsWhen evaluating young children with bilateral severe‐to‐profound sensorineural hearing loss, despite longer exposures to general anesthesia, bilateral cochlear implantations were associated with more improvement in language scores and no differences in other skills compared with those with only unilateral implantation.