Diphallia is an extremely rare condition in which a male is born with two penises, states PubMed Central. The abnormality occurs once in approximately 5 to 6 million births, and since 1609, about 100 cases have been reported. Patients with the condition may have two urethras, bladders and deformed vertebrae.
As the fetus develops in diphallus cases, the pubic tubercle separates, resulting in each phallus having only one body and urethra, or the pubic tubercle cleaves, resulting in each phallus having two bodies and urethras, explains PubMed Central. Physicians have surgically removed duplicate penises and urethras and performed other corrective surgeries on diphallus patients ranging in age from about two days to 14 years old as of 2010.