Young children have a natural amount of fluid in the middle ear, behind the eardrum. With middle ear disease, the fluid doesn’t drain down the narrow Eustachian tube.
As a consequence, bacterial and viral infections develop in the back of the nose and throat and this causes hearing problems.
Inserting grommets (or tympanostomy tubes) helps prevent recurrent ear infections because the fluid can be drained, allowing a free flow of air to the middle ear.
The grommets don’t have to be removed surgically. Sometimes they’re rejected quite quickly but it usually takes quite a few months for this to happen spontaneously - it can be up to 18 months. In the meantime the eardrum seals quite normally.
However, it may not always be necessary to insert grommets. A large study at the Children's Hospital of Pittsburgh followed over 6000 healthy babies and toddlers who were advised to have grommet surgery. The babies were divided into two groups: one having immediate operations or another group that waited for six months. The study, reported in the New England Journal of medicine, found that only a third of the group of children that waited needed to have the operation at all.
And when the children's language, intellectual development and behaviour were measured at three years, there were no differences between the groups. So results show that it may be safe to watch and wait, and in many instances it seems, nature will take care of the fluid itself.