Five Things You Should Know About Breast Pain and Swelling

by PJ Hamel Patient Expert

Many women experience breast pain and swelling at least once over the course of their lifetime. Here are the five most common causes – and what you should do about each.

You're feeling some discomfort in one breast. This discomfort soon turns to pain. You take a look in the mirror; one breast, the painful one, is definitely larger than the other. What do you do?

First, don't panic. Though you may need to see a doctor, understanding what's causing your symptoms is the first step to feeling better.

Cyclical pain and swelling

How to identify: Your breasts become painful and swollen sometime during the two weeks prior to your menstrual period. Cyclical pain and swelling usually occur in both breasts, though one may be more affected than the other.

Cause: Hormones are the culprit. When you ovulate at mid-cycle, estrogen causes your breasts to produce new cells and increase their blood supply, in preparation for a possible pregnancy. These extra cells and blood can produce pain and swelling, from ovulation until your period starts – sometimes more so in one breast than the other.

What to do about it: If the pain and swelling don't become significantly more marked over time, and aren't accompanied by redness, heat, or other signs of infection, wait up to 2 weeks to see if your period starts. Once your period begins, the pain and swelling should gradually dissipate. If they don't, see your doctor.


How to identify: You miss your period. Sometimes early in pregnancy you can continue to have light periods, however. The best way to identify pregnancy is via a pregnancy test.

Cause: Your body is growing your breasts, and increasing their blood supply, in preparation for you nursing your baby.

What to do about it: Once you know you're pregnant, see a doctor. S/he'll let you know the best ways to deal with breast pain and swelling, which might include cold compresses and over-the-counter painkillers.

Breast infection

How to identify: Your breast will probably feel warm and look red, as well as being swollen and painful. There may be redness in a wedge shape radiating from the nipple. You may also notice swollen lymph nodes in your armpit, or feel fatigued, ill, and/or run a temperature.

Cause: Germs and bacteria can enter the breast from small cracks in the skin, especially around the nipple. They can also enter the breast through the nipple itself. A blocked milk duct can become a breeding ground for bacteria and result in breast infection. Mastitis is the most common type of breast infection; it usually occurs in nursing mothers, though non-lactational mastitis is also a possibility if you're not nursing.

What to do about it: See a doctor as soon as possible. Breast infections need to be treated with antibiotics; left untreated they can result in breast abscesses, which may require surgery.

If the drug your doctor prescribes doesn't start to reduce the pain and swelling within a few days, let him or her know; you may be dealing with bacteria requiring a different antibiotic.

Fibrocystic change

How to identify: Your breast is painful, and you may feel a large lump; but it doesn't appear red or swollen, and you don't feel other symptoms that might indicate an infection. The pain and lump may be more prevalent just before your period, but may not disappear entirely over the course of the month.

Causes: Extra breast cells are produced when you ovulate, and then die off. Over the course of many menstrual cycles, a type of scar tissue (or benign tumor) called a fibroadenoma may develop as a result of this process. This solid mass may become large enough to press on nerves and cause pain. Fluid-filled breast cysts may also become large enough to hit a nerve, and/or stretch the tissue around them, causing pain.

What to do about it: See a doctor; s/he can determine exactly what's causing the pain, and decide on treatment, which may include removing the fibroadenoma or draining the cyst. In the meantime, try eliminating caffeine – coffee, tea, chocolate, and certain soft drinks – from your diet. Caffeine can increase breast swelling. Use over-the-counter pain relievers to reduce pain.

Inflammatory breast cancer

How to identify: The symptoms of inflammatory breast cancer (IBC) mimic those of breast infection: pain, redness, heat, swelling. In addition, you may experience itchiness, and a distinctive skin texture similar to the dimpled skin of an orange.

Causes: Like all breast cancers, the exact cause of IBC is unknown. You can lower (though not eliminate) your risk of breast cancer by maintaining a healthy weight, exercising, and minimizing alcohol consumption.

What to do about it: Your doctor will very likely treat you with antibiotics first, as s/he'll assume your symptoms are caused by an infection. If antibiotics don't have any effect, then you'll need to have a biopsy to confirm or eliminate IBC. The IBC Research Foundation recommends biopsy after one week of unsuccessful treatment with antibiotics. If your doctor seems to be taking a "wait and see" approach, bring up the possibility of IBC, and ask about a biopsy.

Breast cancer survivor and award-winning author PJ Hamel, a long-time contributor to the HealthCentral community, counsels women with breast cancer through the volunteer program at her local hospital. She founded and manages a large and active online survivor support network.

PJ Hamel
Meet Our Writer
PJ Hamel

PJ Hamel is senior digital content editor and food writer at King Arthur Flour, and a James Beard award-winning author. A 16-year breast cancer survivor, her passion is helping women through this devastating disease. She manages a large and active online survivor support network based at her local hospital and shares her wisdom and experience with the greater community via