ObjectiveOtitis media with effusion (OME) is a common finding in pediatric cochlear implant(CI) candidates and may be managed by inserting ventilation tubes. This study aimed to compare postoperative complication rates in children who underwent CI without and with OME, including patients who were treated without and with ventilation tube insertion. MethodsA population-based retrospective cohort study was conducted, including all CI patients, under ten years of age, at our institution, between 2007 and 2020. The study's population was divided into three groups based on their middle ear status at CI: 1) OME previously treated with VT, 2) untreated OME, and 3) normal-aerated ears. Postoperative complications of the groups were reviewed and served as our primary outcome measure. ResultsOf the 257 implanted ears included, 53, 42, and 162 ears belonged to the VT-treated OME, untreated OME, and aerated groups, respectively. Acute mastoiditis (AM) rate was significantly higher in the OME group compared to the aerated groups (9.5 % vs. 2.5 %, p = 0.0134) and in the VT-treated compared to the untreated OME groups (15.1 % vs. 2.3 %, p = 0.0356). Similarly, the rate of developing chronic suppurative otitis media without cholesteatoma (CSOMWC) was significantly higher in the OME compared to the aerated groups (12.6 % vs. 2.5 %, p = 0.0011) and in the VT-treated compared to the untreated OME groups (18.8 % vs. 4.7 %, p = 0.0366). Other complications rated were very low and similar between the groups. No other statistical difference was found between the groups. ConclusionVT insertion in pediatric CI candidates with OME increased postoperative AM and CSOMWC. We believe that, at least in our population, VT introduction prior to CI, for OME, surgery should be avoided.