Clogged Ducts and Breastfeeding: What to Avoid (and What Helps)

Breastfeeding is often described as natural, but no one tells you how quickly something “normal” can turn painful. Clogged ducts are one of the most common challenges new moms face. Sharp, tender, frustrating lumps can appear out of nowhere, making every feeding feel harder than it should. 

And while many clogs come from things like missed feedings or pressure on the breast, some triggers are far less obvious. Adhesives in stick-on pasties. Chemical-heavy nursing bras. Even products marketed as “nursing friendly” can sometimes create the perfect setup for a blockage.

One mom learned this the hard way after wearing pasties to dinner during pregnancy, only to wake up the next morning with her first clogged duct. Unfortunately, her experience isn’t unusual, and it’s absolutely worth talking about. 

How Clogged Ducts Happen When Breastfeeding

A clogged duct develops when milk can’t move freely through the breast, and that blockage can come from several different sources. Sometimes it’s simple pressure, like sleeping on one side too long or wearing a bra that compresses breast tissue. Other times, a missed or delayed feeding allows milk to build up behind a duct. Inflammation can also narrow these tiny passageways, making it harder for milk to flow. Issues like a shallow latch, ineffective pumping, or changes in the baby’s feeding schedule can also contribute.

When a duct becomes clogged, you’ll usually feel a tender lump, localized swelling, or redness. Some parents describe shooting pain or discomfort during letdown, and many notice reduced milk output on the affected side. If the clog isn’t relieved, it can progress to mastitis, a much more serious condition marked by fever, chills, body aches, and widespread breast inflammation.

A Real-Life Story: How Stick-On Pasties Triggered a Clogged Duct

While we’re talking about the causes of clogged ducts, here’s a quick story that inspired this blog post. A mom in late pregnancy, already producing early colostrum, decided to wear stick-on pasties for a night out. Nothing unusual. Nothing dramatic. Just a simple wardrobe choice. But by the next morning, she woke up with a painful, swollen lump in her breast: her first clogged duct. The only thing that had changed was the pasties.

Adhesives, especially chemical-heavy glues, can trap heat, block airflow, irritate the skin, and create subtle but significant pressure on delicate breast tissue. That combination can interfere with how milk flows through the ducts, contributing to the very kind of restricted flow and inflammation that can narrow and clog milk ducts.

The Hidden Risks of Chemical Adhesives and PFAS-Laden Nursing Bras

As the new mom experienced, something as seemingly minor as stick-on pasties can create the perfect conditions for a clogged duct, as adhesives often contain chemical compounds that can cause harm. But the concern doesn’t end with pasties. 

Recent testing found that more than half of the nursing bras evaluated contained signs of PFAS, the so-called “forever chemicals” used in stain- and water-resistant finishes. PFAS are linked to hormone disruption, immune system effects, fertility issues, and developmental risks in infants. These chemicals also don’t break down easily and can accumulate in the body.

Research shows that ingredients in personal-care products, including those worn or applied directly on the skin, can enter the bloodstream and even breast milk. Combine that with heat, pressure, and irritated tissue near the milk ducts, and you’ve got a recipe for inflammation that makes unwanted clogs more likely.

While not every product is intentionally treated with chemicals, parents deserve safer, more transparent options, especially for items worn so close to sensitive breast tissue.

What to Avoid to Keep Ducts Clear

To keep ducts clear and comfortable, try to avoid the following:

• Stick-on pasties or sticky nipple covers during pregnancy and breastfeeding. They trap heat and create harmful pressure.
  
• Tight clothing, molded cups, or underwire bras that compress breast tissue.
  
• Chemical-heavy products near the chest, such as PFAS-containing bras, fragranced lotions, and chemical sprays.
  
• Aggressive massage, extreme heat, or over-emptying the breast can worsen swelling and irritation.
  
• Skipping or delaying feedings or pumping sessions is a significant trigger for clogged ducts.
  

What Helps in Preventing Clogged Ducts While Breastfeeding

When a clogged duct strikes, the goal is simple: reduce inflammation and get milk flowing again. Frequent, comfortable milk removal is the cornerstone of relief. That means continuing to breastfeed or pump often, starting on the affected side to encourage better drainage. Switching up feeding positions, trying “dangle feeding,” and ensuring a deep latch can also help shift how milk moves through the breast.

Cool compresses also help. They calm swelling far more effectively than excessive heat, which can worsen inflammation. Pair that with light, sweeping motions (not deep, forceful massage) to nudge fluid toward either the armpit or nipple, depending on where the clog originates. Some parents also swear by the BAIT method (breast rest, Advil, ice, Tylenol) for short-term relief.

For recurring clogs, lecithin or probiotics may offer added support. And yes, the sliced-frozen-potato trick is real (it worked for the new mom who had clogged ducts from the pasties she wore). Many parents find it surprisingly soothing for reducing surface inflammation.

If symptoms worsen or fever, chills, or spreading redness appear, seek medical care promptly, as these may be signs of mastitis.

The Bra You Wear While Pregnant or Breastfeeding Matters

The bra you wear during pregnancy and breastfeeding can directly influence breast health. Pressure from tight bands, molded cups, or underwires can restrict milk flow, while chemical exposure from PFAS-treated fabrics or synthetic adhesives adds another layer of risk. Breast tissue is especially vulnerable during lactation, and your bra sits directly over the milk ducts that keep breastfeeding moving smoothly. Toxin-free nursing lingerie matters. 

JulieMay offers a safer alternative to chemically-laden bras. All of our products are made with organic cotton and pure silk, and are free of adhesives, synthetic dyes, and PFAS. Each piece is breathable, non-restrictive, and hypoallergenic. Our Elysia front-closure full-cup bra, for example, is perfect for breastfeeding moms looking for comfort, easy access, and a little breathability in their everyday bra. 

Clogged ducts are an incredibly common bump in the breastfeeding road, but with the proper support, they’re also highly preventable. By understanding what triggers inflammation and choosing products that are safe and gentle on your skin and ducts, you can give yourself a healthier feeding experience. 

Prioritizing breathable, toxin-free fabrics can make a real difference, especially when they come into direct contact with such sensitive tissue. Explore our bra collections to learn how they can help you feel your best throughout breastfeeding and beyond.