What causes ear infections in babies?

In the first year of life, the most common age for getting ear infections is approximately 9 months. The head is smaller and the tube leading from the head to the nose, which is called the Eustachian tube, often gets blocked from a cold, or a virus, and all the secretions. When that swelling happens, you get increased fluid or pressure in the inner ear, and any bacteria that are present can grow and cause pressure and pain, and that's an ear infection.

It usually comes after a cold, so if your child is getting more colds, they're more likely to get more ear infections. Increased exposure to colds often occurs through larger groups of children. So a family with lots of children or a day-care setting where there's a lot of exposure to illnesses will increase your baby's chance of getting ear infections.