A third nipple has been discovered on the foot of a young woman – with medical staff believing the case may be the first of its kind.

Up to five per cent of people are thought to suffer from the condition although most extra nipples tend to be located above the waist.

Featuring in a report in scientific journal Dermatology Online, researchers believe that the unusual positioning of the four centimetres in diameter nipple may mean it is completely unique.

The report reads: "A 22-year-old woman sought medical care for a lesion in the plantar region of her left foot, a well-formed nipple surrounded by areola and hair.

"Microscopic examination of the dermis showed hair follicles, eccrine glands, and sebaceous glands.

"Fat tissue was noted at the base of the lesion. Clinical and histopathologic findings were consistent with the diagnosis of supernumerary breast tissue, also known as pseudomamma.

"To our knowledge, this is the first report of supernumerary breast tissue on the foot."