Penile agenesis is a birth defect in humans, occurring about once in 5 6 million male births, in which a male child is born without a penis. A partner condition is testicular or gonadal agenesis. This is when a male child is born without gonads and consequently develops no testes. Penile agenesis occurs often as a consequence of Testicular agenesis, but the reverse is never the case. Most patients in both cases have no known family history, and those who have an otherwise normal male anatomy.