Having three nipples means you have what doctors call a supernumerary nipple, and it’s far more common than most people realize. Up to 6% of the U.S. population has at least one extra nipple, making it one of the most frequent minor birth variations. In the vast majority of cases, it’s completely harmless.
Why Some People Have Extra Nipples
During early development in the womb, every embryo forms two “milk lines,” which are ridges of tissue running from the armpits down to the groin on both sides. Nipples normally develop from just one spot on each line, but sometimes the tissue at another point along that line doesn’t fully recede. The result is an extra nipple that’s present from birth, even if you don’t notice it until later in life.
This isn’t a mutation or a sign that something went wrong during development. It’s simply a minor variation in how the milk lines resolved. Extra nipples are actually more common in men than in women, and they tend to appear more often on the left side of the body than the right.
What a Third Nipple Looks Like
Most extra nipples are much smaller than your regular nipples, which is why many people mistake them for moles or birthmarks. They can be pink or brown, and the central part is usually slightly raised off the skin. Some have a small dimple in the center, which is one of the easiest ways to tell them apart from a mole.
Third nipples almost always appear somewhere along those original milk lines, so they’re most commonly found on the chest or abdomen below the regular nipples. Less frequently, they can appear higher up toward the armpit. They can show up on one side or both, and some people have more than one extra.
If you’re unsure whether a small bump is an extra nipple or a mole, a doctor can tell by examining it closely. Under magnification, extra nipples have a distinctive ring of fine lines around the outside (similar to the texture of an areola) and often a pale, scar-like area in the center. These features don’t appear in moles.
The Different Types
Not all extra nipples look the same. A classification system identifies eight different forms, ranging from a complete extra breast with nipple, areola, and underlying gland tissue all the way down to just a small patch of hair along the milk line. The most common type is a nipple only, without any areola or breast tissue underneath. Some people have just a small circle of darker skin (an extra areola) with no raised nipple at all.
The type matters because extra nipples that have glandular breast tissue beneath them can occasionally respond to hormonal changes. During pregnancy or menstruation, they may become tender or swell slightly. In rare cases, extra nipples with enough glandular tissue can even produce small amounts of milk. A nipple-only type, which is the most common, typically causes no symptoms at all.
Does It Signal Other Health Problems?
For decades, some medical literature suggested a link between extra nipples and kidney or urinary tract abnormalities. This idea led some doctors to recommend kidney screening for anyone with a supernumerary nipple. However, larger and more rigorous studies have weakened this association considerably. Most current guidelines don’t recommend routine kidney screening based solely on having an extra nipple, especially when there are no other symptoms or findings.
On its own, a third nipple is not associated with any increased health risk. The tissue can, in very rare cases, undergo the same changes that normal breast tissue can, so if you notice any unusual growth, discharge, or pain at the site, it’s worth having it evaluated. But this is uncommon enough that routine monitoring isn’t necessary for most people.
Removal Is Optional and Straightforward
There’s no medical reason to remove a third nipple unless it’s causing discomfort or you want it gone for cosmetic reasons. If you do choose removal, the procedure is typically quick and done under local anesthesia in an outpatient setting. A doctor numbs the area with an injection, removes the tissue, and closes the site. You’ll have a small scar that fades over time.
Because removal is considered cosmetic, insurance generally doesn’t cover it. If your doctor has confirmed that the bump is a harmless extra nipple, there’s no urgency to act. Many people live their entire lives with a third nipple and never think twice about it.