Most of us are aware that the biological purpose of the female breast is breastfeeding; before becoming pregnant, however, we probably don’t think of our breasts as much more than just parts of our bodies.
Our bodies go through incredible changes to prepare our breasts for breastfeeding. Some of these changes are well known. Others can be surprising, or even totally unexpected. One surprise some moms encounter is feeling lumps under their armpits during this time. This phenomenon, known as milk duct in armpit, might sound unusual, but it’s actually a normal occurrence for many breastfeeding women.
As female breast development takes place, during puberty and pregnancy, some people might notice breast tissue in unexpected places, including in the armpits.
If you are a mother who has noticed milk ducts in your armpit while breastfeeding, don’t worry.
It’s normal and much more common than you would think.
Here are some frequently asked questions about milk ducts in the armpit.
#1. Why do I have breast tissue in my armpit?
Although it might seem strange, it’s normal for the breast to have tissue that extends into the axilla (armpit). Axillary breast tissue occurs in around 6% of the population.
At 6 weeks gestation, when you were a tiny embryo in your mother’s womb, milk lines began to develop, starting from your underarms. These lines travelled down both sides of your torso and extended all the way to your groin.
From 16 weeks gestation, the ‘tails’ at both ends of these lines started to regress. In some fetuses, though, the line doesn’t fully regress at either end, and leaves the ‘tail’.
Tissue that extends into the armpit is called axillary tissue or ‘the tail of Spence’.
#2. Do I have milk ducts in my armpit?
During pregnancy, the level of hormones that help your body make milk is 10-20 times higher than it was before pregnancy.
This cocktail of progesterone, estrogen and prolactin triggers your milk ducts to expand quite extensively. The ducts begin to branch out within the breasts. They can stretch to reach any ‘tails’ of breast tissue along the milk line.
So, yes, it is possible to have milk ducts in your armpit. Motherhood is a weird and wonderful adventure. Consider the number of radical changes your body has experienced since you started your pregnancy and breastfeeding journey.
By comparison, a little extra breast tissue isn’t usually a big problem.
#3. How do I get rid of excess breast tissue in my armpit?
There is no medical reason to remove excess breast tissue in the armpit.
For some people, the extra tissue can cause pain or embarrassment, particularly if there is swelling, a blockage or an obvious enlargement in the armpits.
For comfort, or for aesthetic reasons, the excess breast tissue can be surgically removed. Removal is usually performed by surgical incision, liposuction or a combination of the two.
#4. Can breastfeeding cause armpit pain?
A common cause of pain from breastfeeding is engorgement. This is when the milk ducts become overfilled with milk and there is build up.
Sometimes a milk duct in your armpit can become engorged, causing pain in the armpit while you are breastfeeding.
Pain relief for engorgement in the underarm is treated in the same way as engorged breasts are treated. Use cool compresses and breastfeed your baby frequently.
For more tips on relieving engorgement you can read BellyBelly’s article Engorgement – Relief for Breast Engorgement.
#5. Will swelling in the armpits go away naturally?
If there’s extra breast tissue in your armpit – and possibly extra milk ducts, too – it might become more obvious during pregnancy or after your baby has been born, when your body begins to produce breast milk for your baby.
If you experience postpartum engorgement, it could result in swollen armpits. Engorgement is not only due to the onset of your breast milk supply, but also due to a greater volume of cellular fluids and an increased flow to blood vessels in the whole breast.
Engorgement is common while breastfeeding is being established. If you notice your armpits swollen at the same time as you are experiencing postpartum engorgement, it’s very likely to resolve once your milk supply has settled.
If the swelling in your armpits has increased in size substantially, because of pregnancy or breastfeeding, you could expect them to return to their pre-pregnancy state, eventually, just as your breasts will.
#6. Can losing weight reduce swelling in the armpits?
Just like regular breast tissue, axillary breast tissue is made up of fibrous and fatty tissues.
If you’re overweight, a healthy diet and regular exercise will affect the amount of fat that’s stored in the body.
Just as a healthy diet and regular exercise won’t cause your breasts to disappear completely, neither will they get rid of excess breast tissue under your arm.
Losing weight, however, might be enough to the alter the appearance of the axillary tissue or reduce the discomfort.
#7. Can breast milk cause armpit lumps?
Lumps in the breast are common while breastfeeding. Because breast tissue can extend to the armpit, it’s also possible to get lumps in the armpit, for the same reason.
As mentioned earlier in this article, the most likely cause is engorgement, if your baby isn’t removing milk from the breast efficiently. Most early engorgement resolved itself within 24-48 hours of your milk coming in.
If you’re experiencing difficulties with your baby latching and effectively removing milk, an International Board Certified Lactation Consultant (IBCLC) can give you guidance to help get breastfeeding off to the best start. An IBCLC is an expert in the field of breastfeeding.
#8. How do I get rid of armpit lumps from breastfeeding?
Just like breast lumps from breastfeeding, lumps in the armpit should be relatively easy to treat.
Some effective ways to smooth out clogged milk ducts in armpit while breastfeeding are:
- Warm compresses
- Massage, towards the nipple
- Warms baths and showers
- Frequent milk removal (breastfeeding or pumping).
If there’s a more persistent lump that doesn’t change in size or shape with any of these methods, you should schedule a check-up with your doctor. Your doctor might order breast imaging to confirm that any lumps in your armpit are benign.
For more information on managing blocked ducts, you can read BellyBelly’s article Clogged Milk Duct | 3 Tips To Unplugging Your Ducts.
#9. What if a blocked duct in the armpit doesn’t go away?
A persistent blocked duct can potentially lead to mastitis or a breast abscess.
If you have any of the following symptoms in addition to a blocked duct in the breast, it could be mastitis:
- Red streaks or red skin on the breast
- Pain while breastfeeding
- Fever, chills or body aches.
For more information on mastitis, you can read BellyBelly’s article Mastitis | 9 Painful Signs, Symptoms And Treatment.
Breast lumps and breast cancer
In rare cases, a lump in the breast or armpit might indicate something more serious, such as breast cancer.
To rule this out, your doctor might perform an ultrasound, mammogram, CT scan, MRI scan or needle biopsy on the lump.
The good news is none of these procedures should interrupt breastfeeding.
For more information about breast cancer screening, you can read BellyBelly’s article Breast Cancer Screening | Why Breast Exams Are Important.
