Blocked ducts, what to do about a sore lump in your breast

Almost every week someone shows me a lump in their breast that they have been attacking. Deep massage with their knuckles, a hot flannel, an electric toothbrush pressed against it because of something they read. They arrive with bruising, and a lump that is bigger than when they started. I understand exactly why, because that is the advice most of us were given for years. It has changed, and the new advice is much gentler.

What a blocked duct actually is

The old picture was of a duct plugged with milk, like a blocked pipe that needed clearing. We now understand it differently. The area around the duct becomes inflamed and swollen, and that swelling squeezes the duct from the outside. The milk is not stuck behind a plug so much as pushed on by tissue that is puffy and irritated.

That change matters, because it explains why forceful massage makes things worse. Pressing hard on inflamed tissue creates more inflammation and more swelling, which narrows the duct further. You are not clearing a blockage, you are bruising a breast.

What it feels like

• A firm, tender area or lump, often wedge shaped, that you can feel from the outside.
• The skin over it may look pink or red, or darker, purplish or browner than the skin around it if you have brown or Black skin, and it may feel warm. On darker skin the colour change can be hard to see at all, so go by heat, firmness, swelling and pain rather than colour.
• Feeding on that side can be uncomfortable, and the milk may flow more slowly.
• You feel generally well in yourself, with no fever.

That last point is the one to hold on to. Feeling well, with a sore lump, points to a blocked duct. Feeling unwell, shivery, achy and hot, points towards mastitis, and you can read more in Engorgement and mastitis.

What helps

• Keep feeding normally. Feed responsively on both sides. There is no need to feed obsessively on the affected side, and doing so can increase supply there and make the swelling worse.
• Cold, not heat. Use a cold flannel or a cold gel pack over your clothing between feeds. Cold reduces swelling. Heat increases blood flow to an area that is already inflamed.
• Take ibuprofen if you can, as it treats the inflammation rather than just the pain. Paracetamol can be taken alongside it. Both are compatible with breastfeeding.
• Light lymphatic sweeping. Rest your fingers flat on the skin and sweep very gently towards your armpit, with no more pressure than you would use to stroke a cat. You are moving fluid under the skin, not milk inside the breast.
• Check the latch, because a shallow latch drains the breast less well and makes blockages more likely to come back.
• Look at what is pressing on you. Underwired bras, a bag strap across the chest, a sling, or sleeping on one side. Repeated pressure on one part of the breast is one of the commonest causes I see.

What to stop doing

• Deep massage and digging. It bruises the tissue and worsens the swelling.
• Heat before feeds. Only very briefly, if at all, to help the milk let down.
• Electric toothbrushes and vibrating devices. These do real damage and I have seen the bruises they leave.
• Pumping extra "to clear it". More removal signals more milk, which is the opposite of what an over-full, inflamed breast needs.
• Skipping feeds on that side. Milk still needs to move, just normally.

Why they keep coming back

If you are getting blockage after blockage, the lump is a symptom rather than the problem. The usual causes are an oversupply, a baby who is not draining the breast well because of the latch, long gaps between feeds, or something pressing on the breast. Treating each lump as it appears is exhausting and never ends. It is worth working out which of those is driving it, and you can read more in Oversupply and a fast let-down and Latch and nipple pain.

When to get medical help

That last one matters. Most lumps in a breastfeeding breast are to do with milk, and they soften or move after a feed. A lump that stays exactly the same needs looking at properly, in the same way any breast lump would. Being pregnant or breastfeeding does not protect you from other breast problems, and nobody will think you are wasting their time.

How a consultation helps with recurring blockages

If this keeps happening, the useful visit is not the one where I show you how to rub a lump. It is the one where we work out why your breast keeps getting into that state. I watch a full feed, look at how well your baby drains the breast, and go through the practical things that never get asked about, including what you sleep in, what you carry, and how long the gaps are getting overnight. Most people I see for repeated blockages have one fixable cause running underneath, and once it is dealt with the lumps stop rather than being managed.