Last reviewed 01/2018
Imperforate anus is a congenital cause of intestinal obstruction, bladder and sexual dysfunction. Its describes a spectrum of abnormalities affecting the anorectal area. The anus of the newborn baby must be always checked for the presence patency in the neonatal examination.
Imperforate anus affects 1 in 4000 new babies. In males, the most frequent abnormality is imperforate anus with a recto-urethral fistula, followed by perineal and rectovesical forms. In females, rectovestibular fistula is most common followed by perineal fistula with persistent cloaca. In 5% of cases there is no fistula. There is a higher than average incidence of other congenital malformations, for example, oeosphageal atresia.
The risk of a couple with one affected child having a second child with imperforate anus is about 1%.