Blocked ducts and mastitis are complications women can experience when breastfeeding. In this post we will discuss the symptoms and ways to treat each condition as well as exploring the defining features that set them apart.
Mastitis
Technically mastitis can be categorised into two types, depending on if a woman is breastfeeding or not. Lactational mastitis is the type that occurs during breastfeeding. It is classified as inflammation of the breast tissue and affects around 13% of women.
Mastitis causes breast tissue to become tender and swollen, often creating a hard wedge shape in the affected area. Skin can become red and hot to touch and there may be pain when breastfeeding. It often involves flu-like symptoms such as fever, aches and chills.
There is no standardised clinical definition for mastitis, however, it is usually diagnosed via the symptoms listed above. Often there is a bacterial infection present, however, some sources don’t believe this is a defining feature.
Signs that appear to be linked to increased risk of mastitis include: poor latch and positioning at the breast (this limits babies ability to drain all areas of the breast leading to milk build up in some areas), sore or cracked nipples (these introduce an entry point for bacteria), smoking, poor nutrition, poor hygiene and wearing a tight fitting bra.
How to treat mastitis?
At-home treatments can be helpful for mastitis if it is identified and responded to early. These include:
- Using a cold compress on the area to soothe the pain and inflammation.
- Continuing to feed baby from the breast that is affected. Focusing on a deep latch will encourage better drainage of the breast (be careful not to feed more from this side as you may stimulate more supply).
- Use a warm flannel or warm water in the shower to encourage milk flow (be careful not to apply a lot of heat).
- Take paracetamol to manage your fever and ibuprofen for the pain and swelling.
If symptoms persist or worsen over 24 hours from initial symptoms, seek help from your GP.
Blocked Ducts
Blocked ducts can occur regularly when milk builds up in the ducts creating a blockage. Blockages lead to insufficient drainage of milk from the affected area and can cause a lump or swelling behind the blocked area. They most often occur when attachment and positioning at the breast isn’t great, leading to a lack of drainage in certain areas of the breast.
Blocked ducts are not associated with infection but can lead to mastitis if not treated appropriately.
Symptoms of blocked ducts include a tender lump on the breast, breast tenderness and sometimes small white blisters occur on the nipple. Occasionally babies become fussier on the breast because milk flow is impaired by the blockage. Blocked ducts don’t coincide with a change in general health, fever or hot and red areas on the breast.
How to treat blocked ducts?
- Continue feeding baby with the affected breast to encourage sufficient draining.
- Try feeding in different positions to drain the affected part of the breast (e.g. if the blockage is on the outer, lower section of the breast feed baby in rugby position so their chin can stimulate the affected area).
- Massage the breast as baby feeds to encourage the blockage to loosen or release.
- Use a warm compress before feeding to encourage milk flow.
- Avoid wearing a tight bra or anything restrictive on your breasts.
References
Gondkar, P., Kumar, H., & Patel, K. (2024). Incidence and risk factors associated with human mastitis. Health Sciences Review, 12, 100191. https://doi.org/https://doi.org/10.1016/j.hsr.2024.100191
Kvist, L. J. (2010). Toward a clarification of the concept of mastitis as used in empirical studies of breast inflammation during lactation. J Hum Lact, 26(1), 53-59. https://doi.org/10.1177/0890334409349806
Lawrence, R. A. (1990). The puerperium, breastfeeding, and breast milk. Curr Opin Obstet Gynecol, 2(1), 23-30.
NHS. (2023). Mastitis. (Accessed on 12/2/25)
Wilson, E., Woodd, S. L., & Benova, L. (2020a). Incidence of and Risk Factors for Lactational Mastitis: A Systematic Review. J Hum Lact, 36(4), 673-686. https://doi.org/10.1177/0890334420907898
Wilson, E., Woodd, S. L., & Benova, L. (2020b). Incidence of and Risk Factors for Lactational Mastitis: A Systematic Review. J Hum Lact, 36(4), 673-686. https://doi.org/10.1177/0890334420907898
