Non-infectious mastitis and milk stasis
It is thought that most cases of non-infectious mastitis are caused by milk stasis; milk stasis occurs when the milk is not properly removed from your breast.
Milk stasis can be caused by:
- your baby not being properly attached to your breast during feeding,
- your baby having problems suckling the milk out of your breast, or
- your baby having infrequent feeds.
Milk stasis can lead to the milk ducts in your breasts becoming blocked, as the breast milk is not being properly and regularly expressed.
Blocked milk ducts can also occur as a result of pressure on the breast, such as tight-fitting clothing or an over-restrictive bra.
Experts are still unsure why breast milk can cause the breast tissue to become inflamed. One theory is that it may be due to the presence of cytokines in breast milk. Cytokines are special proteins that are used by the immune system and are passed on to your baby in order to help them resist infection. It may be the case that your immune system mistakes these cytokines for a bacterial or viral infection and responds by inflaming the breast tissue in an attempt to stop the spread of infection.
Infectious mastitis
Fresh human milk does not normally provide a good environment for bacteria to breed in. But if the milk ducts become blocked, the milk can then stagnate and an infection can occur.
Exactly how the bacteria enter the breast tissue has not been conclusively proven. Some suggestions are:
- bacteria that normally live harmlessly on the skin of your breast enter through a small crack or break in the skin of the breast, or
- bacteria that are present in the baby's mouth and throat can be transferred during breastfeeding.
Infectious mastitis in non-breastfeeding women
Occasionally, infectious mastitis can develop in women who are not breastfeeding. Smokers in their late 20s or early 30s are most commonly affected.
It is thought that there is something in tobacco smoke that can damage the milk ducts and make them vulnerable to infection.
Mastitis can also develop after nipple piercing. You should be able to prevent this by only using professional piercing studios that are registered with your local authority.
