New Guidance for Mastitis

Emily Oster

10 min Read Emily Oster

Mastitis. If you’ve had it, the word itself prompts a reaction. When I mentioned the topic in our ParentData Slack channel, one team member commented, “Just the thought of this gives me a fever.” For me, the salient memory is adhering to the advice to feed the baby first from the affected breast. I love my son, but I did not love him at that moment.

For those who have no idea what I am talking about, here’s a quick overview. Mastitis, in general, refers to a condition in which the breast is swollen, hot, and painful. It can occur outside of breastfeeding but is most common during that period, when it’s referred to as “lactational mastitis.” Lactational mastitis occurs in something between 2% and 10% of breastfeeding women and is part of a much larger continuum of related discomforts.

I’m going to talk today about new guidelines for treatment from the Academy of Breastfeeding Medicine (ABM), and in these new guidelines they have an excellent graphic, which I’ve included below.

A flow chart to show the causes of mastitis.

Some of the words here are a little jargony (“hyperlactation” = oversupply; “dysbiosis” = bacterial overgrowth), but what I like about the graphic is the illustration of the continuum.

Mastitis often starts with a combination of an oversupply of milk, and bacterial growth. Oversupply of milk can occur for various reasons — it is common in the early weeks of breastfeeding, during weaning, or at any time when the cadence of nursing changes and your supply needs to adjust. The oversupply can lead to milk stagnating in the breast, which can cause bacterial growth. The excess bacteria and milk can lead to a narrowing of the milk ducts, which can then progress to inflammatory mastitis. That can then progress to bacterial mastitis or (rarely) to abscess.

When mastitis progresses to the later stages, it can lead to systemic symptoms — fever, fatigue. In these cases, there is widespread agreement that it is necessary to treat it with antibiotics, and antibiotic treatment is effective in nearly all cases. And it is completely fine to continue to nurse while on antibiotics.

Important note: Please do not be anxious or reluctant to ask your doctor about this. Do not just suffer in silence!

What this image and discussion make clear, however, is that there are stages before that point at which it may be possible to reverse course. Mastitis, in early stages, can and often does resolve on its own. To enhance that possibility, women are typically prescribed what we might call “supportive care.”

We can divide the supportive care advice into two parts. The first is what we might call the “non-specific” or “obvious” part. This includes advice like “drink fluids and rest” (easy to say, harder to do with a baby), take ibuprofen or Tylenol for pain, and avoid wearing tight sports bras.

The second is advice that is more distinct to the breast. Looking over the popular Mayo Clinic website and the advice in UpToDate, a website for doctors, we see four key recommendations:

  • Apply warm compresses to the breast or take a warm shower.
  • Breastfeed frequently, starting with the affected breast.
  • Use a pump to express milk between feedings.
  • Massage the breast area.

This has been the standard advice. It is the advice I got when breastfeeding. However: in the past several weeks, the ABM has come out with new guidelines, and, on these particular pieces of advice, they pretty much say the exact opposite. Here is my summary of their version:

  • Apply ice to the breast. Warm compresses might make things worse.
  • Continue to breastfeed, but do not favor the affected breast; in some cases, use only the unaffected breast.
  • Minimize breast pump usage; do not “pump to empty” the breasts.
  • Avoid deep massage of the breasts.

I had a feeling a bit like the change in allergen advice — this does not just walk back the existing recommendations; it literally says the opposite. The ABM says the existing advice might make things worse! Naturally, I got curious about what changed. Was there some big new study? Did our understanding of breast biology alter in some way?

My attempts to figure out the answer to that led me down something of a guideline rabbit hole, or more like an infinite guideline loop. For example, in the UpToDate entry on this topic, they provide a number of citations for their advice. Those citations, though, rather than containing evidence on particular recommendations, are just other restatements of the advice. These statements cite back to other statements, and so on.

In several cases, the guidelines I found linked back to earlier guidelines from the ABM. But those guidelines were superseded by the new guidelines that were just released. So … did that mean that actually everyone agreed with the new guidelines? It was unclear.

Beyond this, when there were studies linked, the evidence was underwhelming. For example, in the new guidelines, the authors state: “The use of warm showers and antipyretics [fever-reducing medications] did not improve mastitis outcomes in a randomized controlled trial.” This statement seemed quite compelling to me, and is perhaps the strongest direct refutation of the older advice. When I went to the citations for this claim, though, I found a randomized trial of acupuncture for treatment of mastitis. The trial rejected the value of acupuncture, but I didn’t see anything on showers.

Searching through the text, I found the evidence in support of the warm shower claim. One of the groups took more warm showers than the others and didn’t have their mastitis resolve any more quickly. This is weak evidence — it certainly isn’t randomized — and the samples in this paper are small (200 women in total over three treatment groups).

In the end, I found it difficult to find compelling data to support either side of any of these claims. (More on my feelings on that travesty at the end of this piece.)

This is slightly different, however, from saying there is no information to support any of the claims. The Academy of Breastfeeding Medicine article makes a weak case for their changes based on data, but a much stronger one based on logic.

As I noted at the top, mastitis is part of a continuum that often begins with an oversupply of milk and ductal inflammation. The logic in the article is simple: if you want to address the problem, you need to address these causes. This means downregulating supply, especially from the affected breast, and reducing inflammation. It is these observations, rather than experimental data, that point to the conclusions.

Hot versus cold for treating mastitis

Any kind of topical temperature change on the breast would be designed to treat inflammation. In general, inflammation is more often treated with ice rather than heat. This is a generic statement about all inflammation (it’s why I have these ice shoes to put on after I run), but we can see why it would apply here too. If you want to treat inflammation, ice is the initial go-to choice. If you do not want to put ice directly in your shirt, there are breast-specific cold packs. 

Which breast? Pump versus not?

The advice about which breast to start on and whether to pump are intimately related to the issues of oversupply.

To the extent that oversupply of milk contributes to mastitis, treating it will involve lowering supply. Breast milk supply responds to demand. If you nurse and pump more in general, your body learns you need to produce more milk and makes more of it. Similarly, if you nurse and pump more on one side, that side will be more active. This is something you may be familiar with if your child has a favored breast. One of my kids vastly preferred to nurse on the right side, and it led to a very lopsided look (it mostly got better).

By extension of this theory, though, if you take a breast that already has an oversupply and you encourage more supply, you might make the problem worse. Much of the standard advice has this feature. Encouraging people to start nursing on the affected side will increase production on that side. Pumping between feedings, or “pumping to empty,” also generates more supply.

In contrast, starting nursing on the other side and avoiding or limiting use of the pump will help the breast regulate. This is a bit of a balance. Especially with an engorged breast, completely ignoring it will also be very painful. An approach of “pumping (or hand-expressing) to comfort” (rather than to empty) may be a way to generate the right feedback without stimulating supply.

Massage for breast pain relief?

Massage is actually the trickiest part of this. There is general agreement that very light “sweeping” massage can be effective and relieve pain. However, in some cases people will more aggressively massage in an effort to remove a perceived milk “plug.” This will not work, though. Mastitis isn’t caused by a particular stuck piece of milk in a tube. The breast has many, many ducts, and they get inflamed, but not plugged-up. As a result, aggressively massaging to remove a milk plug doesn’t make sense.

And, further, when you already have inflamed tissue, deep massage can possibly make things worse, by increasing the inflammation and damaging the tissue.

In summary

Based on the logic of breasts and breastfeeding, these updated guidelines make some sense.

Most key and important seems to be the guidance on supply. If you take nothing else from this discussion, it should be that stimulating more supply in the affected breast is not a good idea.  

Beyond that, what I took from this was a feeling of frustration. A huge share of breastfeeding women will experience some form of inflammation or mastitis during their breastfeeding journey. All of these people are looking for relief, and we should be giving them advice based on evidence. Despite this: the data is so limited that literally people are getting the exact opposite advice, depending on who gives it. 

My call to action here, then, is for someone to do a randomized trial. I do not think this would be all that hard. Recruit people with mastitis, randomize into different protocols, figure out if ice really works better than heat. Figure out the right protocol to relieve engorgement without generating more oversupply. See if it is possible to improve knowledge about massage. I hope someone will do this. If you need help recruiting a sample, please let me know.

Final note

If you want more on this, or to understand it all better, I highly recommend the detailed description of the updated guidelines, which you can find here. It contains a number of extremely helpful visuals, along with a fairly clear discussion of the underlying medical issues.

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The AAP’s guidelines recommend sleeping in the same room as your baby “ideally for the first six months.” However, the risk of SIDS is dramatically lower after four months, and the evidence in favor of the protective effect of room sharing is quite weak (both overall and even more so after four months). There is also growing evidence that infants who sleep in their own room by four months sleep better at four months, better at nine months, and even better at 30 months.

With this in mind, it’s worth asking why this recommendation continues at all — or at least why the AAP doesn’t push it back to four months. They say decreased arousals from sleep are linked to SIDS, which could mean that babies sleeping in their own room is risky. But this link is extremely indirect, and they do not show direct evidence to support it.

According to the data we have, parents should sleep in the same room as a baby for as long as it works for them! Sharing a room with a child may have negative impacts on both child and adult sleep. We should give families more help in navigating these trade-offs and making the decisions that work best for them.

#emilyoster #parentdata #roomsharing #sids #parentingguide

The AAP’s guidelines recommend sleeping in the same room as your baby “ideally for the first six months.” However, the risk of SIDS is dramatically lower after four months, and the evidence in favor of the protective effect of room sharing is quite weak (both overall and even more so after four months). There is also growing evidence that infants who sleep in their own room by four months sleep better at four months, better at nine months, and even better at 30 months.

With this in mind, it’s worth asking why this recommendation continues at all — or at least why the AAP doesn’t push it back to four months. They say decreased arousals from sleep are linked to SIDS, which could mean that babies sleeping in their own room is risky. But this link is extremely indirect, and they do not show direct evidence to support it.

According to the data we have, parents should sleep in the same room as a baby for as long as it works for them! Sharing a room with a child may have negative impacts on both child and adult sleep. We should give families more help in navigating these trade-offs and making the decisions that work best for them.

#emilyoster #parentdata #roomsharing #sids #parentingguide
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Watch the full segment at the link in my bio 🔗

#tamronhall #tamronhallshow #emilyoster #parentingsupport #workingparents

It was an absolute pleasure to be featured on the @tamronhallshow! We talked about all things data-driven parenting and, in this clip, what I call the plague of secret parenting. To balance having a career and having a family, we can’t hide the fact that we’re parents. If mothers and fathers at the top can speak more openly about child-care obligations, it will help us all set a new precedent.

Watch the full segment at the link in my bio 🔗

#tamronhall #tamronhallshow #emilyoster #parentingsupport #workingparents
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My guest on this episode, @everodsky, has come up with a solution here, or at least a way for us to recognize the problem and make our own solutions. I’ve wanted to speak with Eve for ages, since I read her book Fair Play. We had a great conversation about the division of household labor, one I think you’ll get a lot out of!

Listen and subscribe to ParentData with Emily Oster in your favorite podcast app 🎧

#emilyoster #parentdata #parentdatapodcast #parentingpodcast #householdtips #fairplay #invisiblelabor

Invisible labor. It’s the work — in our households especially — that has to happen but that no one sees. It’s making the doctor’s appointment, ensuring birthday cards are purchased, remembering the milk.

My guest on this episode, @everodsky, has come up with a solution here, or at least a way for us to recognize the problem and make our own solutions. I’ve wanted to speak with Eve for ages, since I read her book Fair Play. We had a great conversation about the division of household labor, one I think you’ll get a lot out of!

Listen and subscribe to ParentData with Emily Oster in your favorite podcast app 🎧

#emilyoster #parentdata #parentdatapodcast #parentingpodcast #householdtips #fairplay #invisiblelabor
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Good news: fancier vitamins are not better.  Folic acid is the most important prenatal ingredient. Iron (with vitamin C) and DHA are also nice to have. Other included ingredients have only weak or no evidence to support their use. (If you do not consume animal products, add B12, plus a few others depending on your diet.)

Vitamins are just vitamins. Any prenatal vitamin that contains these is enough. 

Comment “Link” for a DM to an article with everything you need to know about prenatal vitamins.

#emilyoster #parentdata #prenatalvitamins #pregnancydiet #pregnancytips

Prenatal vitamins 💊 If there is any product that seems designed to prey on our fears, it’s this one. You’re newly pregnant and you want to do it right. Everyone agrees you need prenatal vitamins, so you get them. But do you want to be that person who just… buys the generic prenatal vitamins?

Good news: fancier vitamins are not better. Folic acid is the most important prenatal ingredient. Iron (with vitamin C) and DHA are also nice to have. Other included ingredients have only weak or no evidence to support their use. (If you do not consume animal products, add B12, plus a few others depending on your diet.)

Vitamins are just vitamins. Any prenatal vitamin that contains these is enough.

Comment “Link” for a DM to an article with everything you need to know about prenatal vitamins.

#emilyoster #parentdata #prenatalvitamins #pregnancydiet #pregnancytips
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#parentdata #emilyoster #newborncare #parentingadvice #parentingtips

When it comes to introducing your newborn to the world, timing matters. It’s a good idea to minimize germ exposure in the first 6-8 weeks; after that, it’s inevitable and, very likely, a good idea! This doesn’t mean you need to be trapped inside. The most significant exposure risks are from seeing other people at home — family, etc. These interactions are not infinitely risky, but they do pose more risk than a walk or a trip to the grocery store, since they involve closer interaction. Think simple and make sure everyone is washing their hands before holding the baby. 💛

#parentdata #emilyoster #newborncare #parentingadvice #parentingtips
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The first edition of Hot Flash is out now! Comment “Link” for a DM to learn more about the late-reproductive stage.

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🔥 Hot Flash from ParentData is a weekly newsletter on navigating your health and hormones in the post-reproductive years. Written by Dr. Gillian Goddard, Hot Flash provides all of the information you need to have a productive, evidence-based conversation about hormonal health with your doctor.

#emilyoster #parentdata #hotflash #perimenopause #womenshealth

The first edition of Hot Flash is out now! Comment “Link” for a DM to learn more about the late-reproductive stage.

There are times when we expect hormonal shifts. Our reproductive lives are bookended by puberty and menopause. We discuss those changes often because they are definitive and dramatic — a first period is something many of us remember clearly. But between ages 13 and 53, our hormones are changing in more subtle ways. During the late-reproductive stage (in your 40s), you can expect a lot of changes in your menstrual cycle, including the length and symptoms you experience throughout. It’s an important time in our lives that is often overlooked!

🔥 Hot Flash from ParentData is a weekly newsletter on navigating your health and hormones in the post-reproductive years. Written by Dr. Gillian Goddard, Hot Flash provides all of the information you need to have a productive, evidence-based conversation about hormonal health with your doctor.

#emilyoster #parentdata #hotflash #perimenopause #womenshealth
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Now tell me in the comments: what’s a parenting move you’ve made recently that feels right to you?

#parentingcommunity #parentingsupport #parentingquotes #emilyoster #parentdata

There are plenty of reels telling you how to parent. Plenty of panic headlines saying that “studies show” what’s best for your kid. Even good data, from a trusted source, can send us into a spiral of comparison. But I want you to remember that no one knows your kid better than you. It’s important to absorb the research, but only you will know the approach that works best for you and your child. 💙

Now tell me in the comments: what’s a parenting move you’ve made recently that feels right to you?

#parentingcommunity #parentingsupport #parentingquotes #emilyoster #parentdata
...

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Listen and subscribe to ParentData with Emily Oster in your favorite podcast app 🎧

#parentdata #parentdatapodcast #emilyoster #emilynagoski #comeasyouare #cometogether #longtermrelationship #intimacy #relationships

Let’s talk about sex (after) baby! Today on the podcast, I was lucky enough to speak with @enagoski about her new book on sexual connection in long-term relationships. Especially after having kids, this is something many people struggle with. Emily tells us to stop worrying about what’s “normal” and focus on pleasure in its many forms.

Listen and subscribe to ParentData with Emily Oster in your favorite podcast app 🎧

#parentdata #parentdatapodcast #emilyoster #emilynagoski #comeasyouare #cometogether #longtermrelationship #intimacy #relationships
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Comment “Link” for a DM to an article on another common formula question: should you throw away old formula powder?

#emilyoster #parentdata #babyformula #babyfeeding #parentingstruggles

Ever wondered if you can safely use leftover baby formula? 🍼 The CDC says to throw out unused formula immediately because of the risk of bacterial growth. However, research suggests that bacterial concentrations do not appreciably increase after 3, 12, or even 24 hours at refrigerator temperatures. Good news! This means there’s not a strong data-based reason to throw out formula right away if you store it in the fridge.

Comment “Link” for a DM to an article on another common formula question: should you throw away old formula powder?

#emilyoster #parentdata #babyformula #babyfeeding #parentingstruggles
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#emilyoster #parentdata #parentingtips #parentingadvice #newparents #parentingcommunity

What’s the most important piece of advice for new parents? Here’s one answer, but I want to hear from you! Share your suggestions in the comments ⬇️

#emilyoster #parentdata #parentingtips #parentingadvice #newparents #parentingcommunity
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What's in the bag of a Vagina Economist? 👀 Someone please tell me this looks familiar to you.

What`s in the bag of a Vagina Economist? 👀 Someone please tell me this looks familiar to you. ...

Comment ”link” for a DM to learn more about tongue ties 🔗

Breastfeeding is often difficult, especially at the start. For babies with tongue ties, many infants (and their moms) struggle to get the hang of a good latch. This can lead to painful nipples and to inefficient feeding, and then low weight gain.

So what does the data say about the increasingly common practice of cutting tongue-ties in infants to improve breastfeeding success? Several weeks ago, @nytimes published a long and quite scary article on this topic.

After diving into the data, here is what I found. There is limited evidence that frenotomy procedures improve breastfeeding efficacy and the harms of the procedure are minimal. Many women do report that it alleviates pain and helps them with breastfeeding. However, it should not be a first-line treatment for breastfeeding problems.

#parentdata #emilyoster #tonguetie #tonguetiebabies #breastfeedingsupport

Comment ”link” for a DM to learn more about tongue ties 🔗

Breastfeeding is often difficult, especially at the start. For babies with tongue ties, many infants (and their moms) struggle to get the hang of a good latch. This can lead to painful nipples and to inefficient feeding, and then low weight gain.

So what does the data say about the increasingly common practice of cutting tongue-ties in infants to improve breastfeeding success? Several weeks ago, @nytimes published a long and quite scary article on this topic.

After diving into the data, here is what I found. There is limited evidence that frenotomy procedures improve breastfeeding efficacy and the harms of the procedure are minimal. Many women do report that it alleviates pain and helps them with breastfeeding. However, it should not be a first-line treatment for breastfeeding problems.

#parentdata #emilyoster #tonguetie #tonguetiebabies #breastfeedingsupport
...

Tag a friend who needs to hear this 💛 For many choices in parenting, there is no one right answer. We can use research and data to make informed decisions, but ultimately, it won’t tell you what to do. Only you can decide what will be best for your kids and your family.

I’m here to remind you to take a deep breath and trust yourself. I’ll be here to support you along the way. 

Thank you to everyone who submitted videos, including:
@sarah.consoli
@jess_lynn627
@nicolevandenwills
@thedrblair
@ncbenedict29
@haleycimini
@iamkellysnodgrass
@calesse_smith
@garnet__gordon
@jencoopgaiser87
@danigirl18c
@jamielundergreen
@carly_comber
@thecelebratingmama
@emilyannbynum
@eeliz413

#emilyoster #parentdata #parentingadvice #parentingsupport #parentingquotes

Tag a friend who needs to hear this 💛 For many choices in parenting, there is no one right answer. We can use research and data to make informed decisions, but ultimately, it won’t tell you what to do. Only you can decide what will be best for your kids and your family.

I’m here to remind you to take a deep breath and trust yourself. I’ll be here to support you along the way.

Thank you to everyone who submitted videos, including:
@sarah.consoli
@jess_lynn627
@nicolevandenwills
@thedrblair
@ncbenedict29
@haleycimini
@iamkellysnodgrass
@calesse_smith
@garnet__gordon
@jencoopgaiser87
@danigirl18c
@jamielundergreen
@carly_comber
@thecelebratingmama
@emilyannbynum
@eeliz413

#emilyoster #parentdata #parentingadvice #parentingsupport #parentingquotes
...

Congratulations on making it through another year of panic headlines! We’ve had some doozies this year, like aspartame causing cancer and the perils of white noise, but these headlines are very often based on poor data. Correlation does not equal causation. There will certainly be more panic headlines in 2024, but ParentData is here to debunk them for you.

#emilyoster #parentdata #happynewyear2024 #panicheadline #datadriven

Congratulations on making it through another year of panic headlines! We’ve had some doozies this year, like aspartame causing cancer and the perils of white noise, but these headlines are very often based on poor data. Correlation does not equal causation. There will certainly be more panic headlines in 2024, but ParentData is here to debunk them for you.

#emilyoster #parentdata #happynewyear2024 #panicheadline #datadriven
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