Complete anal membrane in a female: a rare malformation and indication for prone cross-table lateral radiograph.

Magnetic resonance imaging (MRI) of a 27 week gestation female fetus suggested an abnormal rectum. Subsequent examination of the term newborn confirmed an imperforate anus present in the normal position. No meconium was seen on the perineum by 18 hours. A prone cross-table lateral radiograph confirmed that rectal gas was present 3 mm beneath the membrane leading to the diagnosis of complete anal membrane, and an anoplasty rather than a colostomy was performed.