Milk stasis – not infection – is the main cause of mastitis

holding_babyPrior to my brush with it, I thought that mastitis was caused by a bacterial infection. This is not completely unreasonable, given that this is precisely how numerous ‘health’ websites define it (FreeMD, eMedicineHealth, HealthSquare to name just a few). When you consider that the symptoms of mastitis can include a fever as well as redness, lumps and pain in the breasts, and treatment can involve antibiotics, the definition seems to make sense.

Unfortunately, it turns out to be somewhat misleading. Whilst bacterial infection may play a part in mastitis, it is in fact inflammation of the breast tissue that is at the root of the condition, and causes the majority of the symptoms. The World Health Organization describes mastitis as ‘an inflammatory condition of the breast, which may or may not be associated with infection’1. They summarize the uncertain relationship between bacterial infection and mastitis as follows:

Many lactating women who have potentially pathogenic bacteria on their skin or in their milk do not develop mastitis.
But:
Many women who do develop mastitis do not have pathogenic organisms in their milk.

This basically means that you can be carrying the bacteria associated with mastitis – and even have it in your milk – without developing the condition, and conversely, you can succumb to mastitis when there is no evidence you’re carrying the bacteria.

So, if mastitis isn’t due to an infection, what does cause it? It appears that the inflammation that characterizes mastitis is a consequence of ‘milk stasis’: milk is produced, but then remains in the breast, rather than coming out during feeding. Milk stasis can occur for many reasons, including blockages in the ducts, a decrease in feeding frequency and poor attachment1,4. It’s also possible that stress might play a role, by both increasing milk production and delaying the letdown reflex2. Why milk stasis goes on to cause inflammation isn’t so clear, though it could result from inflammatory substances found in milk irritating the breast tissue, or an immune reaction to certain milk proteins3.

Although bacterial infection is not often the primary cause of mastitis, it is sometimes thought to exacerbate the symptoms3. Determining the precise role it plays, however, is a tricky business. Firstly, it is very hard to ensure that milk cultures are sterile, so it isn’t always possible to know that the bacteria found in a woman’s milk haven’t in fact come from her skin when the sample was taken1. Secondly, as stated above, harmful bacteria can be found in the milk of women who don’t have mastitis, indicating that there is not a simple cause and effect relationship between the two. One possibility is that mild changes initiated by milk stasis may be exacerbated by bacterial activity: symptoms could be considered to be on a scale, from a reduction in milk output but no pain (known as subclinical mastitis), to breast abscess and severe pain, with increasing amounts of bacterial involvement as you move from one end to the other3.

What does all this mean if you find yourself suffering from mastitis? Perhaps the most important thing to remember is that the symptoms are probably due to a milk flow problem, so your top priority should be to address any causes of this. This might include making sure your baby is properly latched on, feeding more frequently and emptying the breast properly at each feed. Many doctors also choose to treat mastitis with antibiotics, although there is a lack of consensus as to which ones to use, and even whether it’s appropriate to use them at all (see when should mastitis be treated with antibiotics?). Whether or not you take medication, the most important thing is to keep the milk moving. Whilst feeding with mastitis doesn’t appear to pose a risk to you or your baby, stopping could well do: not only will it make the symptoms worse, but it will almost certainly jeopardize your milk supply5. Mastitis is a common reason for giving up breastfeeding, but it needn’t be – focus on sorting out your feeding technique and you should hopefully make a rapid recovery.

  1. Mastitis: causes and management. World Health Organization; 2000.
  2. Mediators Inflamm. 2008;2008:298760.
  3. Arch Dis Child. 2003 Sep;88(9):818-21
  4. Cochrane Database Syst Rev. 2009 Jan 21;(1):CD005458.
  5. Am Fam Physician. 2008 Sep 15;78(6):727-31.

My mystery rash is mastitis!

telephoneSix weeks down the line, I felt I had really turned a corner with breastfeeding. My nipples were definitely starting to heal, and C seemed to be getting plenty of milk. Admittedly, she was pretty noisy at times (‘clicking’ noises were a regular occurrence) but as the milk was clearly going down her I didn’t really worry when I noticed a pinkish patch starting to appear on the inside of my left breast.

A couple of days passed, and the patch had turned into a definite rash: a wedge-shaped stripe running from the top right to the nipple of my left breast. It didn’t hurt, and I still wasn’t overly perturbed, but I thought I should probably find out what it was.

By this stage, contact with the health visitor had long since ceased, and although I had planned to ask at the weighing clinic, in the end it just didn’t seem the right time. In any case, my recent experience had taught me that the most likely response of any health professional would be to recommend I speak to a counsellor, so I decided to pre-empt them, and got on the phone.

This time I decided to call La Leche League. Like the NCT counsellor I had spoken to previously, the lady who answered the phone had a pretty brusque bedside manner. Never mind – I needed answers, not sympathy. When I had described my symptoms, she replied, without skipping a beat, ‘ah, classic early stage mastitis.’ What?! But it didn’t hurt! This, she agreed, was unusual, but she suspected it was because I had caught it so quickly. If I left it any longer, the pain would definitely arrive. How old was my baby?, she asked. When I said 6 weeks, I could almost hear her wearily shaking her head at the other end of the phone. ‘This is such a common problem at this stage. Women think they’ve really got the hang of breastfeeding and become complacent, so they don’t adequately respond to the fact that their baby has started to get much heavier, and he ends up being poorly attached.’ My heart sank. I had been thinking that I’d pretty much got it sorted. I’d been a bit worried about the clicking noises, but had put them down to the torrent that was released by my letdown these days. Whether or not that was the cause, it seems I should have heeded them as a potential sign of a poor latch.

I put down the phone relieved that I had caught the problem early, but somewhat panicked at the thought of what it might turn into if I didn’t (a fever and a potential hospital admission. No pressure then.) Although her advice – to avoid further inflammation by keeping the breast as empty as possible – seemed straightforward enough, following it involved solving a latch problem that I hadn’t even realized existed. Feeling pretty fed up, I picked up C, and set about perfecting my breastfeeding technique all over again.

Breast shells: preserving your modesty

shellsWhen I suffered substantial nipple damage in the early weeks of breastfeeding, the ‘moist wound healing’ route didn’t prove effective (see nipple solutions 1: doing nothing), so allowing a bit of air to circulate was the obvious alternative option. Walking around topless wasn’t always practical (although I have to admit it happened quite a bit – apologies to my neighbours) so wearing breast shells provided a workable solution. They seemed to help, psychologically at least, but as I used them on both breasts pretty much all the time, I have no idea whether they really had any effect on the healing process, or the pain I experienced when breastfeeding.

Is there any clinical evidence of their effectiveness? The short answer is not really, although that may be partly because there is very little research looking at the use of breast shells in this context. A couple of studies have reported on the effect of shells used in combination with lanolin, but they obviously don’t tell us anything about the utility of shells in keeping nipples dry12.

There is one small study, conducted some time ago, which evaluated the use of breast shells on their own as a means of alleviating nipple pain3. 20 women who had just started breastfeeding and were experiencing pain were asked to wear a single breast shell whenever they weren’t feeding (the other nipple was kept shell-free, to serve as a control). On the second and fifth days of using the shells the women were asked to rate the level of pain they were experiencing on a 5 point scale, from mild (1) to excruciating (5) during the first two minutes of a feed, and for the period between feeds. Although the mean pain score was higher for the nipple without the shell on day five, this difference was not statistically significant. The study did have an interesting anecdotal result, however. Despite the fact that the shells didn’t lessen pain, 80% of the women said they would consider using them again, so the majority of women felt that they offered some kind of help. The precise nature of the benefit isn’t described in detail, but it appears to be related to improved general comfort and decreased friction with clothing.

Problems mentioned by some women (although it is not reported how many) focused on concerns about the ‘hardness’ of the shell, and the pressure it exerted on breast tissue. The possibility of pressure on milk ducts is also mentioned by shell manufacturers, who advise against using breast shells for extended periods (although they also market the same action as a short term means of relieving engorgement). Whilst the possibility of negative consequences arising from pressure caused by shells can’t be dismissed, there don’t yet appear to have been any reported in the clinical literature, so the extent to which a problem actually exists isn’t clear.

The lack of research in general into either the benefits or drawbacks of breast shells makes it difficult to draw any firm conclusions regarding their use. Whilst problems arising from pressure on breast tissue cannot be dismissed, as yet, these have not been widely reported. There isn’t any data showing they improve nipple pain, although there is anecdotal evidence that they ease discomfort.  You may find they take up too much room in your already overstretched bra, or you might find the way that they stop it rubbing against your nipples provides a little relief. If the latter is the case, breast shells do have one undeniable advantage: they allow you to minimize friction, without having to resort to indecent exposure…

  1. Arch Pediatr Adolesc Med. 1998 Nov;152(11):1077-82.
  2. J Perinat Educ. 2004 Winter;13(1):29-35.
  3. J Nurse Midwifery. 1988 Mar-Apr;33(2):74-7.

Will breastfeeding leave you with a little less lift?

smug_mumGiven the number of celebrities who have recently publicized their decision to breastfeed (Angelina Jolie, Christina Aguilera and Jennifer Garner to name but a few), it was disappointing to read in February’s British Vogue that Cheryl Cole is put off by the effect it might have on her breasts. ‘I want to breastfeed,’ she declared, ‘but I’ve seen what it can do, so I may have to reconsider.’

Cheryl’s concern is a common one. Whilst breastfeeding may be the healthiest option, it isn’t seen as the aesthetically pleasing one: not only does it desexualize your breasts (using them for something other than attracting men – surely not!?), it is also rumoured to leave you with a little less ‘lift’ than you might have had if you’d gone down the formula route.

Is a little sagginess really the price you have to pay for giving your children the healthiest start in life? Not necessarily, according to a recent study by a plastic surgeon at the University of Kentucky1. The surgeon and his colleagues examined data from all the women who had come to the UK HealthCare clinic seeking aesthetic breast surgery over an eight year period. They considered a number of factors, including the number of pregnancies the women had had and whether they had breastfed, and determined the degree of ‘ptosis’ (that’s droop to you and me) from pre-operative photos.

Factors which appeared to increase ptosis included higher body mass index, pre-pregnancy bra size, age, and smoking. The number of pregnancies a woman had gone through was also linked with ptosis, but whether she had breastfed, interestingly, was not.

So it seems that although having children may leave you less perky (probably in more ways than one), you can breastfeed safe in the knowledge that any loss of elasticity has already happened either in pregnancy or in the days shortly after giving birth. Cheryl, bear this in mind if you’re thinking about having children, and if you’re really worried, consider adopting. In the meantime, it might be sensible to give up smoking…

  1. Aesthet Surg J. 2008 Sep-Oct;28(5):534-7.

Insufficient milk: all in the mind?

milk pouring from bottle to glassIf you’ve ever felt that your baby isn’t satisfied with your breast milk, you’re not alone: ‘not enough milk’ is the reason mothers provide more than any other for giving up on breastfeeding1. A recent review in the Journal of Nursing Scholarship reports that the problem is huge2: Insufficient Milk Supply (IMS) is the primary cause of 35% of instances of early breastfeeding termination. If we apply this figure to the UK, where 51% of women start breastfeeding initially, but have stopped by 6 months3, it equates to an alarming 1 in 6 babies being potentially malnourished, were it not for the option of formula milk.

Or does it? The review, which collates the research in this area over the last 10 years, reveals that the term IMS is actually used interchangeably with PIM – Perceived Insufficient Milk – making it very difficult to determine how many women really aren’t providing enough milk for their babies, as opposed to those who just believe they aren’t.

Although research in this area is lacking (according to the review, ‘the accuracy of maternal perceptions, or PIM, in relation to actual milk supply has not been determined’), there is some data that gives an idea of the relationship between the two. A study conducted in Chicago followed 96 mothers who planned to exclusively breastfeed for at least 12 weeks4. To determine how much milk their babies were taking on board, the women were asked to weigh them before and after every feed and record the results in a log book. Whether or not the women thought their milk supply was adequate was determined in a series of telephone interviews.

Unfortunately, the paper doesn’t report exactly how the mothers’ perception of their milk supply related to their actual output (the goal of the study was to identify factors that predicted whether women were breast or formula feeding at 12 weeks). It is, however, possible to work out roughly from the data they do include that at least 17% of the women whose supply was adequate at the final recorded weighing session went on to report PIM in the interview two weeks later. Whilst the possibility that the milk supply of all these mothers suddenly dropped cannot be ruled out, neither can the possibility that it was the perception of their supply, rather than their actual supply, which suffered.

One thing that the Chicago study did demonstrate strongly, as did the other research in the review, is that if women think they aren’t producing enough milk (regardless of how accurate this perception is), they are more likely to stop breastfeeding, or supplement with formula. The study also showed that the women most likely to report PIM (and to have a genuinely inadequate supply) were those who breastfed their babies fewer than 8 times a day. As breastfeeding regularly is itself vital to maintain production1, anything that compromises this (such as formula supplementation) can quickly reduce supply, turning the perception of insufficient milk into a reality. If you’re genuinely worried, you should see your doctor. In the meantime, keep in mind that the best way to stop supply dwindling is to increase, rather than decrease, the frequency of your breastfeeding.

For further information about this problem, see not enough milk: the ‘symptoms’ you don’t need to worry about.

At the end of the study (12 weeks postpartum), 28 mothers were using formula either completely or partially, and 69 were breastfeeding exclusively. At week 6, (when actual milk output was calculated for the final time), 19 of the formula feeders, and 65 of the breastfeeders were shown to have an adequate supply. In the 8 week interview, however, 20 of the formula feeders and 6 of the breastfeeders reported PIM, which means that assuming that the 13 women whose supply was genuinely low at week 6 reported PIM at week 8, the other 13 mothers (11 formula feeders and 2 breastfeeders) perceived their supply to be low when not long before it had been shown to be fine. Unfortunately, as the measures of actual and perceived insufficiency weren’t taken at the same time, it isn’t possible to work out exactly how much of the insufficiency is imagined rather than real (more research in this area please!). On the plus side, 6 women who reported PIM at week 8 were breastfeeding exclusively at week 12, so it isn’t impossible to overcome this problem.

  1. Aust Fam Physician. 2006 Sep;35(9):686-9.
  2. J Nurs Scholarsh. 2008;40(4):355-63.
  3. Infant Feeding Survey 2005
  4. J Perinat Neonatal Nurs. 2007 Jul-Sep;21(3):250-5.