Breast milk is made and stored in alveoli in the breast and delivered to the nipple via milk ducts (little tubes). When a baby begins to suckle, oxytocin is released which causes the cells around the alveoli to contract and eject breast milk into the ducts towards the nipple (the let down reflex).
What is a blocked milk duct?
As the name suggests, a blocked (or plugged) milk duct is a tube through which milk can’t flow due to a blockage of some kind. Jack Newman, Canadian paediatrician, explains that incomplete breast drainage may cause thickened milk:
An abundant milk supply plus a baby who doesn’t latch well result in partial “emptying” of the breast. (Of course, a breast is never “empty” since the milk is being made continuously, but in this situation the baby leaves more milk in the breast than might be desirable.) That leftover milk can sit in the breast and thicken, blocking the duct.
A blockage in one duct will create a thickening or lump which may then press on other ducts close by which can narrow or close them too—creating a bigger blockage and slower milk flow for your baby. Once milk is not flowing in one area of the breast it can quickly become uncomfortably engorged and, if this is not relieved, it could develop into mastitis.
Preventing a blocked milk duct
In order to prevent blocked milk ducts try to make sure your baby’s position and latch are as good as possible. Remember to let your baby finish the first breast first before offering the second and use gentle breast massage and compression on any areas that feel engorged while you feed or express.
How to clear a blocked milk duct
Treatment for a blocked milk duct is very similar to ideas for treatment for mastitis—apart from the use of cabbage leaves which Dr Jack Newman says shouldn’t be used for a blocked milk duct:
- Feed your baby often to try to clear the blockage.
- Check your baby is latching deeply and draining the breast thoroughly. If you’re not sure about this contact your IBCLC lactation consultant for help.
- Use breast massage or breast compression to put gentle pressure on the blocked milk duct or any other hard lumpy areas while baby suckles. You could also try massage while pumping.
- Try different breastfeeding positions to help drain the blockage. Unusual positions such as kneeling on all fours to feed the baby lying flat on the floor (dangling the breast over the baby), or having the baby’s chin pointing towards the blockage have helped some mothers.
- Use hot compresses or a heated pad on the blocked milk duct prior to a breastfeed.
- Check whether you have a bleb or milk blister on your nipple which is contributing to the blocked milk duct.
- Take anti inflammatory medication for pain and to reduce inflammation.
- Between feeds, if the area is still sore and engorged, cold therapy can give pain relief and reduce swelling.
- Try to look after yourself, rest and remember to eat and drink.
A blocked or plugged duct will usually resolve in 24-48 hours (Newman, 2014) if it is still there for much longer than this, check with your health professional and be vigilant for signs of mastitis.
Ideas for treating stubborn blocked milk ducts
Jack Newman and Edith Kernerman discuss the possibility of trying ultrasound to treat blocked milk ducts and the dose needed in their article Blocked Ducts and Mastitis.
Check nothing is cutting into the breast such as tight clothing, poorly fitted bras—including nighttime bras, or whether baby carriers, slings or heavy bags are causing any pressure on the breast.
Lecithin is a food supplement which some mothers find useful if they are prone to blocked milk ducts. Dr Jack Newman explains the dosage he recommends:
Lecithin refers to a group of phospholipids that are found in many foods, including egg yolk and soybeans; it is sold as a food supplement in pharmacies and health food stores. It may help to prevent recurrent blocked ducts. We usually recommend 1,200 mg three or four times a day, but some mothers take twice this amount. It comes in capsule form and also as a liquid. We usually recommend the capsule form, since it is easier to swallow.
Recurring blocked milk ducts
If you have had more than one episode of blocked milk ducts you may be wondering why they keep coming back. There are a number of risk factors to be aware of that can increase your chances of this:
- Poor positioning and/or a shallow latch (with or without sore nipples)
- Rrestricting breastfeeds to a schedule instead of on demand
- Using a nipple shield or using a breastfeeding pillow that perhaps are no longer needed
- Previous breast surgery, nipple piercing or any scarring
- A previous episode of mastitis that hasn’t cleared properly or a previous blocked milk duct in the same area making that spot susceptible
- Thrush can be associated with blocked milk ducts (Newman, 2014; Bonyata, 2011)
- Being very stressed or anaemic (Bonyata, 2011)
- Vigorous exercise particularly using the upper arms and chest.
For more comprehensive ideas including whether other supplements such as Vitamin C or Oil of Evening Primrose could help see Dr. Jack Newman’s Guide to Breastfeeding and Kelly Bonyata’s Recurrent Mastitis or Plugged Ducts.
If your blocked milk duct is still there…
A blocked milk duct that isn’t getting smaller after a week or two should be checked out with your doctor for a firm diagnosis. If the blockage is causing any engorgement this could lead to mastitis or even to an abscess if left unchecked. Some breast lumps might not be blocked milk ducts after all e.g. a galactoceole is a milk cyst—your doctor can help with a diagnosis. Most medical tests for diagnosis are compatible with breastfeeding. Work with your doctor and IBCLC lactation consultant to help solve your blocked milk duct and prevent it from returning.