Harlequin Fetus is a term used to describe pictures of infants with harlequin ichthyosis, a rare genetic skin disorder where the skin of an infant is covered with thick pale scales on the body. These plates are extremely painful and tend to crack and split apart very frequently. The thick plates can pull at and distort facial features and can restrict breathing and eating. The baby also has completely red eyes as a result of inverted eyelids. Mutations in the ABCA12 gene cause harlequin ichthyosis.
Due to the revolting nature of these images, they are often used as a bait and switch to trick people into searching this particular image. According to Google Analytics, the search terms "Harlequin icthyosis", "Harlequin fetus", and "Harlequin baby" have been searched since 2003.
On January 16th, 2004, an Urban Dictionary user Bubby the Tour Guide submitted an entry about the image, warning users not to search it up. They described the image as "the most horrifying image of a disease anybody has ever seen." Another Urban Dictionary user submitted an entry for Harlequin Fetus, describing it as "the most severe form of congenital ichthyosis." The entry has received over 500 likes.
NOTE: The following page contains an extremely graphic image!