Tender nipples most often signal a normal hormonal shift, like the kind that happens before your period, during early pregnancy, or at puberty. Less commonly, tenderness points to friction irritation, infection, a medication side effect, or a breastfeeding issue. Pain from cancer is rare when there’s no lump or other suspicious change.
Hormonal Changes Are the Most Common Cause
Estrogen and progesterone directly affect breast tissue density and sensitivity. When levels of both hormones rise together, the effect on breast tissue is more pronounced than when estrogen acts alone, which is why tenderness tends to cluster around specific hormonal events. The tissue itself can swell with extra fluid and grow denser, putting pressure on nerve endings in and around the nipple.
During a typical menstrual cycle, tenderness often starts around ovulation (roughly mid-cycle) and continues until your period begins. This pattern, called cyclical breast pain, is considered clinically insignificant in terms of cancer risk. It can affect one or both breasts, and the intensity varies from cycle to cycle. If your nipple tenderness follows this predictable rhythm, it’s almost certainly hormonal.
Hormone therapy that combines estrogen with progestin also commonly causes breast and nipple tenderness. Oral contraceptives work through a similar mechanism, raising hormone levels in ways that stimulate breast tissue growth.
Early Pregnancy
Breast and nipple tenderness is one of the earliest signs of pregnancy, sometimes noticeable before a missed period. Your breasts may feel similar to how they do before your period but more intense. The nipples can tingle, darken in color, and become noticeably more prominent. Veins across the breast may also become more visible as blood flow increases. These changes begin within the first few weeks after conception and are driven by a rapid surge in progesterone and estrogen that prepares the breast tissue for eventual milk production.
Breastfeeding-Related Causes
If you’re nursing, tender or painful nipples usually trace back to how your baby latches onto the breast. A shallow or improper latch is the most common culprit, and correcting positioning often resolves the pain within a few feeds. An ill-fitting breast pump flange can cause similar irritation.
Nipple vasospasm is another possibility. This happens when blood vessels in the nipple constrict, temporarily cutting off blood flow. You’ll notice the nipple turning pale or white, followed by a deep, radiating pain. Symptoms tend to be worst right after breastfeeding or pumping, or when you move from a warm environment to a cooler one. Oversupply of milk and poor latch both make vasospasm more likely.
Nipple yeast infections (thrush) were long blamed for shooting pain, redness, and cracking during breastfeeding. More recent research has cast doubt on that diagnosis. Current evidence suggests these symptoms are more reliably explained by latch problems, vasospasm, or other mechanical causes rather than a fungal infection.
Infection and Mastitis
Mastitis is a breast infection that causes tenderness, warmth, and swelling, usually in one breast. The skin often reddens in a wedge-shaped pattern, though this can be harder to spot on darker skin tones. You may feel a thickened area or lump, along with a burning sensation that can be constant or flare during breastfeeding. A fever of 101°F (38.3°C) or higher and a general feeling of illness are hallmarks that separate mastitis from ordinary soreness. Mastitis most commonly affects breastfeeding women but can occur in anyone.
Friction and Physical Irritation
Nipple chafing from clothing is surprisingly common, especially among runners. The repetitive motion of fabric rubbing against the nipple during exercise creates raw, stinging irritation sometimes called “jogger’s nipple.” Sweat-soaked shirts make it worse because wet fabric clings and increases friction. Cotton is a particularly common offender once it gets heavy with sweat. Cold weather also plays a role by making nipples more erect and therefore more exposed to rubbing.
Prevention is straightforward: wear lightweight, moisture-wicking fabrics that fit snugly enough to reduce movement against the skin. A well-fitting sports bra helps significantly. Applying petroleum jelly or a runner-specific anti-chafe balm to the nipples before exercise creates a protective barrier. Some runners also use adhesive bandages or nipple covers for longer sessions.
Medication Side Effects
Several categories of medications can trigger breast and nipple tenderness. Common ones include oral contraceptives, estrogen replacement therapy, certain antidepressants (SSRIs like fluoxetine), water pills (diuretics), spironolactone, and some antipsychotic medications. If your nipple tenderness started shortly after beginning a new medication or changing a dose, the timing is worth noting. The tenderness often improves after your body adjusts or if the medication is switched.
Nipple Tenderness in Men
Men experience nipple tenderness too, most often from a condition called gynecomastia, where breast tissue enlarges due to a hormone imbalance between testosterone and estrogen. The tissue may form a noticeable lump behind the nipple that’s tender to touch and moves easily under the skin.
Gynecomastia is extremely common at three life stages: shortly after birth (from maternal hormones), during puberty when estrogen can temporarily outpace testosterone, and after age 50 as testosterone levels decline. More than half of male newborns and adolescents experience some degree of breast enlargement. In most cases it resolves on its own. Certain medications can also cause it, including some heartburn drugs, hair loss treatments, and heart medications. Rarely, gynecomastia can be linked to underlying conditions like pituitary or testicular tumors, or low testosterone production.
When Tenderness May Be More Serious
Breast pain alone is rarely a sign of cancer. According to the American College of Radiology, pain that’s cyclical (tied to your menstrual cycle) or diffuse (spread across more than one quadrant of the breast) is not associated with malignancy and doesn’t require imaging beyond your usual screening schedule.
Pain becomes more worth investigating when it’s focal (concentrated in one specific spot covering less than 25% of the breast), noncyclical, and persistent. Even then, the concern isn’t the pain itself but whether it’s accompanied by other changes. If you notice a lump, bloody or pus-like nipple discharge, a newly inverted nipple, or skin changes that look like eczema on the nipple, those warrant prompt evaluation.
Paget’s disease of the breast is a rare cancer that starts at the nipple and closely mimics eczema, with itching, scaling, crusting, and oozing. It usually affects only one breast. Symptoms may seem to come and go at first but eventually worsen. Because it looks so much like an ordinary rash, it’s often misdiagnosed initially. A rash on one nipple that doesn’t respond to typical skin treatments deserves a closer look.