What causes one side of the meatus to be bigger than the other?

An asymmetrical meatus, or urethral opening, can result from various factors, including anatomical variations, trauma, or inflammation. Conditions like hypospadias, where the urethra opens on the underside of the penis, can lead to an uneven appearance. Additionally, infections or lesions might cause swelling or changes in tissue that affect the size of one side. If the asymmetry is pronounced or accompanied by other symptoms, medical evaluation is recommended.