Understanding the causes of mastitis is an important step toward preventing it. Many breastfed infants are colonized with bacteria from their mothers, which occurs to a greater extent in infants under three months old and those born by cesarean surgery. It’s unclear whether these so-called transient colonization episodes cause some cases of mastitis. Still, if they do occur, they’re more likely to happen when there’s a change in the mother’s diet or her immune system is suppressed temporarily by medications she may be taking.
Most cases of mastitis are caused by changes in the milk other than bacterial contamination. Although there has been little research on this topic, many breastfeeding moms experience mastitis because the udder skin is too tight for milk to flow out easily when the baby sucks. As a result, the baby empties the udder frequently for feedings throughout the day. To decrease chances of developing mastitis, keep your nipples clean and dry after feedings and massage your breast often during feedings with warm, wet hands or a hand pump instead of letting the baby suck on just one nipple at a time.
Why does my breast feel sore or tender when I’m breastfeeding?
The most common reason why a breastfeeding mother feels sore or tender in her breasts is due to engorgement. This is when the milk supply increases significantly after a few days of birth. So while it may feel uncomfortable at first, it usually goes away within a few days.
Engorgement is usually harmless. If you’re breastfeeding indoors (such as at a hospital or daycare), it’s common for your baby’s room to smell like milk because your baby may be spitting out or drooling it onto your breast to get rid of it. If your breast feels pain, take breaks between feedings or put a clean cloth between your breast and your baby’s mouth. If the pain persists, talk to your doctor.
Engorgement is more likely to occur in mothers pregnant for the first time, those who had a difficult pregnancy, and those who were breastfed for less than a month.
Signs and symptoms of mastitis in breastfeeding mothers
- Red, lumpy breast tissue
- Painful breast tissue that may be tender to the touch
- Swollen areola (dark nipple area)
- Increased lumpiness or misshapen breast shape
- Breastmilk that has a salty taste or is not as nutritious as it was before mastitis
- Infrequent or decreased milk production
- Sore or achy breast muscles
- Blocked ducts
- Yellowish, thick-yellow, or greenish breastmilk
- A change in the smell of your breastmilk that’s different from how it smelled before mastitis
- A change in the way your nipple feels, such as if it’s more pointy, softer, or covered in spots
Causes of mastitis for non-breastfeeding mothers
While many cases of breast infection are caused by bacterial contamination of the breast, some cases of mastitis occur for reasons other than bacterial contamination. Some of the most common causes of mastitis in non-breastfeeding mothers include:
- Suppressed immunity from medications, chronic illness, or receiving blood products
- Infections of the breast ducts
- Breastfeeding too frequently (more than once every 3 hours) or with too much pressure or a wrong position
- Hormonal changes during pregnancy or postpartum that weaken the immune response
- Genetic factors that predispose some breastfeeding mothers to develop mastitis
- Viruses that affect the cells that make milk in the ducts
- Certain infections that affect the glands that make milk, such as glandular fever or lymphoma
Causes of mastitis for breastfeeding mothers
The most common cause of mastitis in breastfeeding mothers is an infection in the breast ducts. Breastfeeding mothers are more likely to develop duct infections if they have an underlying condition that weakens their immune system, such as HIV/AIDS, chemotherapy for cancer, or a transplant. Another common cause of mastitis is disrupted milk flow when the nipple is blocked by dried milk, a cracked or torn nipple, or a full breast.
Other causes of mastitis include:
- Breastmilk obstruction is caused by a clogged duct or a lump in one of the glands that release milk into your ducts
- Breastmilk that has a salty or metallic taste that doesn’t go away after you drink some water
Preventing Mastitis
There are many things that you can do to help prevent mastitis. The best way to prevent any infection is to wash your hands frequently, avoid kissing or sharing cups or bowls with people who are sick, and keep your nails short and clean.
Keep your nipples clean and dry after feedings, and massage your breast often with warm, wet hands instead of letting your baby suck just on one nipple at a time.
Summary
Mastitis is an inflammation of the breast tissue. Although most cases of mastitis are caused by bacterial contamination of the breast, some cases occur for reasons other than bacterial contamination. For example, many breastfeeding mothers experience transient colonization episodes when the bacteria on their breasts are from their skin and not from bacteria in the air. The most common reason for these episodes is that the areola is too tight for milk to flow when the baby sucks. You can do many things to prevent mastitis, such as keeping your nipples clean and dry after feedings and massaging your breast with warm, wet hands.
