Chronic ear fluid and recurrent ear infections are usually caused by a blocked eustachian tube. However, there are other factors that might worsen a child’s condition: Exposure to adults who smoke. Drinking from a bottle while lying down (or bottle propping), which can cause milk to enter the middle ear space. Nasal allergies, which can cause more frequent ear fluid buildup. Consider this factor if your child has hay fever, eczema, asthma, or food allergies. Nightly snoring caused by large adenoids. If any of these factors are true for your child, treat or eliminate them before you consider tympanostomy tubes.