Mermaid syndrome, or sirenomelia, is a condition where the legs of a new-born child are fused together. The child may have two feet sticking out to the sides like flippers or no feet at all. The bones of the feet and legs may be missing entirely or fused.
Usually, children with mermaid syndrome die shortly after birth.
The condition occurs along with other abnormalities that affect the kidneys, bladder, genitals and rectum. The lungs may also be affected.
There have only been three reported case of children with mermaid syndrome surviving.
The cause is not known but is generally related to poor prenatal care, illness, or a genetic predisposition.