Supernumerary nipple commonly called “third nipple” is a minor malformation that is present by birth. People with third nipple will have additional tissue in the chest area apart from the common nipples. They are often found on the embryonic milk lines. Sometimes third nipple can occur along the lines of embryonic milk tissue or beneath the regular nipples on the chest.
In most of the cases third nipple would be seen partially with one of the milk tissue involved. Third nipple does not carry any significance clinically and is of no importance. In some cases third nipple is associated with certain types of syndrome like Char syndrome, Turner syndrome and Kaufman Mckusick syndrome.
Occurrence of third nipple is very rare phenomenon. It is found in less than 1.6% of African Americans, 4.5% in Israel, and about 5% in Germans.
A third nipple is often single and in rare cases 3 or more supernumerary nipples have been reported to be present in the same person. Third nipple is found unilaterally and it can be symmetric or asymmetric. In some people it is found above the normal nipples and in other cases below. For some teenage girls, developing breast would hide the third nipple and can be diagnosed only by a doctor.
Studies indicate that 5% of the third nipples are found visibly outside the milk line and is located anywhere on the chest, back or even shoulders or neck. In medical terms, third nipple is known as polythelia and the development of extra breast tissue is called polymastia. For many others third nipple is often present in the form of moles or freckles and does not look like a breast tissue.
Who have the risk of getting a third nipple?
Both men and women can develop a third nipple. For reasons unknown, it runs on families for some people.
Exact cause for the formation of third nipple is not known. It is believed to occur due to Neuregulin 3 NRG3 protein which sends a signal to the cells to develop into breast cells. There are some families who have developed a third nipple for 4 generations successively.
When to see your doctor?
If the presence of a third nipple bothers you or if it secretes milky discharge or if it develops into a lump you need to consult your doctor.
Any doctor can easily detect the presence of third nipple by mere physical exam.
As long as the third nipple does not bother you, you need not go for treatment. If you feel it is undesirable in your body, cosmetic procedures are available to remove it. Your doctor can remove the third nipple using surgical excision or by freezing it with liquid nitrogen (cryotherapy) and use the same procedure for removing moles.
The presence of a third nipple is likely to cause cancer in future. But there is no foolproof evidence to support this theory. The surgeon would also use liposuction method for removing the supernumerary nipple along with breast tissue. You can always make follow-ups visits to your doctor to rule out any unwanted complications. Your doctor would instruct you about the intervals of doing mammography for checking its growth.