Sore nipples are most commonly caused by hormonal shifts tied to your menstrual cycle, friction from clothing, or pregnancy. Less often, the cause is a skin reaction, an infection, or a medication side effect. The soreness is almost always benign, but understanding the pattern and any accompanying symptoms helps you figure out what’s going on.
Hormonal Changes During Your Cycle
The most common reason for nipple soreness that seems to come and go is your menstrual cycle. Estrogen and progesterone levels rise and fall throughout the month, and your breast tissue is highly sensitive to both. Nipples are most likely to feel sore in the week leading up to your period, during the luteal phase when progesterone peaks. Ovulation, which happens roughly mid-cycle, can also trigger a brief window of tenderness.
This type of soreness is called cyclic mastalgia. It affects both sides, often improves once your period starts, and returns the following month in a predictable pattern. If you track your cycle and notice the timing lines up, hormones are the likely explanation. No imaging or testing is needed for cyclic breast or nipple pain as long as you don’t feel a lump and your routine screening is current.
Early Pregnancy
Nipple soreness is one of the earliest signs of pregnancy, sometimes appearing just one to two weeks after conception, before a missed period. Rising hormone levels and increased blood flow to breast tissue make the nipples noticeably more sensitive. The feeling is often described as a more intense version of premenstrual soreness that doesn’t go away when your period would normally start.
This tenderness tends to be strongest during the first trimester and gradually eases as the body adjusts, though some people experience it on and off throughout pregnancy. If your nipples are unusually sore and your period is late, a pregnancy test is the fastest way to rule this in or out.
Friction and Chafing
Repeated rubbing from clothing is a straightforward but often overlooked cause. Runners know this as “jogger’s nipple.” Each stride shifts your shirt slightly across your chest, and over thousands of repetitions the friction can crack and chafe the skin. It’s most common after longer runs, but any sustained physical activity in rough or loose-fitting fabric can do it.
Prevention is simple. Moisture-wicking, snug-fitting tops reduce fabric movement. A well-fitted sports bra adds a layer of protection. Placing a small adhesive bandage over each nipple before a workout creates a direct barrier. Petroleum jelly or anti-chafing balm applied beforehand also keeps clothing from grinding against the skin. If you’re already chafed, keeping the area clean and dry while avoiding further friction is usually enough for healing within a few days.
Skin Irritation and Contact Dermatitis
The skin on and around the nipple is thin and reactive. Soaps, laundry detergents, body lotions, and fabric softeners can all trigger contact dermatitis, leaving the nipple red, dry, or cracked. New bras or tops made from synthetic materials are another common irritant. The soreness in these cases tends to stick around rather than cycling with your period, and you may notice flaking or a rash on the areola.
Switching to fragrance-free detergent, skipping fabric softener, and wearing soft cotton against your chest often resolves the problem within a week or two. If the irritation doesn’t clear up, a dermatologist can help identify the specific allergen.
Breastfeeding-Related Pain
If you’re nursing, sore nipples are extremely common in the first weeks and have a few distinct causes. The most frequent is a shallow or improper latch, where the baby clamps down on the nipple tip rather than taking in a wider mouthful of breast tissue. This creates intense, pinching pain that peaks at the start of each feeding. A lactation consultant can usually correct this in a single visit.
Other breastfeeding causes include milk blebs (a small, painful white spot where a milk duct opening becomes blocked) and vasospasm, where blood vessels in the nipple constrict after feeding, causing a burning or throbbing sensation that can turn the nipple white. For years, nipple yeast infections (thrush) were a standard diagnosis for burning, shooting pain during breastfeeding. Recent research has shifted that understanding significantly. Current evidence shows little to no proof that yeast infections actually occur on the nipple, and the symptoms once attributed to thrush are now more commonly linked to latch problems, vasospasm, or contact irritation.
One Cochrane review found that no single topical treatment clearly outperforms doing nothing for breastfeeding-related nipple pain. Applying expressed breast milk to the nipple showed a short-term benefit over lanolin at four to five days, but the difference disappeared by one week. Lanolin, glycerine gel pads, and multi-ingredient nipple ointments all performed no better than leaving nipples alone. Fixing the underlying cause, especially latch and positioning, matters far more than what you put on the skin.
Medications That Cause Breast Tenderness
Several types of medication list breast or nipple pain as a side effect. Oral contraceptives and estrogen replacement therapy are the most well-known culprits because they directly alter hormone levels. Certain antidepressants in the SSRI class (like fluoxetine), some antipsychotic medications, and the blood pressure drug spironolactone can also cause tenderness. If your nipple soreness started around the same time as a new prescription or dosage change, the medication is worth discussing with whoever prescribed it.
Blocked Ducts and Mastitis
A blocked milk duct causes a firm, tender spot in the breast, sometimes with a visible white bleb on the nipple. It’s uncomfortable but localized and doesn’t make you feel sick. Mastitis is what can happen when that blockage progresses or bacteria enter cracked nipple skin. It brings a distinct combination: a red, warm, painful wedge-shaped area on one breast plus flu-like symptoms including fever (typically 101°F or higher), body aches, fatigue, and headache. Mastitis is almost always one-sided.
The difference matters because simple nipple soreness can be managed at home, while mastitis with fever and systemic symptoms needs medical treatment to prevent an abscess.
Rare but Serious: Paget’s Disease
Paget’s disease of the breast is uncommon, but it’s worth knowing about because it mimics a harmless skin condition. It starts on one nipple only and causes flaky, scaly, or crusty skin that looks like eczema. Other signs include a burning sensation, itching, straw-colored or bloody discharge, a nipple that turns inward, or thickening of the breast skin. It can spread from the nipple to the areola and beyond.
What sets Paget’s apart from ordinary irritation is that it doesn’t respond to standard eczema treatments, it stays on one side, and it persists or worsens over weeks. Any eczema-like change on a single nipple that isn’t improving deserves evaluation.
When Nipple Pain Warrants Imaging
Cyclic soreness that matches your menstrual pattern and involves both sides, with no lump and a normal physical exam, does not require imaging. The situation changes when the pain is noncyclic and focused on one spot. Focal, one-sided nipple or breast pain should prompt diagnostic imaging because of a small but real association with underlying problems. For women 30 and older, that typically means a mammogram. For women under 30, ultrasound is preferred.
Any palpable lump, spontaneous bloody or clear discharge from one nipple, or persistent skin changes that don’t resolve with basic care should also be evaluated with imaging and potentially a tissue sample. These scenarios are uncommon, but they’re the line between “wait and watch” and “get it checked.”