Cloacal exstrophy

Cloacal exstrophy is a severe birth defect wherein much of the abdominal organs (the bladder and intestines) are exposed. It often causes the splitting of both male and female genitalia (specifically, the penis and clitoris respectively), and the anus is occasionally sealed.

It is extremely rare at only 1 in 250,000 births being afflicted with it, and its cause is unknown.