Breastfeeding and thrush: it’s complicated

woman-doing-mathI sometimes feel as if I’ve experienced pretty much every breastfeeding problem going: sore/bleeding/fissured nipples; mastitis (although fortunately only the early stages); not enough milk; too much milk; and a very temperamental let-down reflex. One of the only things I haven’t suffered from is thrush – a fungal or yeast (candida) infection that allegedly causes excruciating nipple and breast pain. I use the word ‘allegedly’ simply because it is not always easy to determine whether the symptoms associated with thrush are definitely caused by a fungal infection, or whether they are in fact down to something else. I am not a thrush doubter – I think there is sufficient evidence to justify taking it very seriously, as does the NHS. Many health professionals who do not specialize in breastfeeding are yet to be convinced, however, as the Mumsnet discussions below testify:

(These are just a drop in the ocean – you will find all manner of breastfeeding ignorance from health professionals on these noticeboards. The GP who suggested a mother might pass mastitis on to her baby deserves a special mention.)

It isn’t just those outside the field who disagree about thrush: within the scientific literature there are conflicting results and opinions, as well as holes in clinical knowledge because the relevant research simply hasn’t been conducted. I’m currently wading through the published work in this area, and am finding it’s actually quite difficult to get to the bottom of the relationship between yeast infections and breastfeeding problems. As it’s important to try to make sense of it though, I’ll be writing several posts on it over the next few weeks, starting with one that attempts to address the controversy that still surrounds the diagnosis.

Hydrogel dressings for breastfeeding: ‘a clinical case study’

medicsIn the moist wound healing post, I discussed a number of peer-reviewed clinical studies that examine whether using dressings or creams to prevent nipples drying out helps them to heal more quickly (short answer: it doesn’t). While I was researching the post, I came across a ‘clinical case study’ on a hydrogel dressing manufacturer’s website, purporting to show the effectiveness of their product. As it is not really research, it wasn’t included in the moist wound healing post, but as it very much tries to appear as if it is, I thought it would useful to write about it anyway.

In the ‘study’, 10 women were supplied with hydrogel dressings within 24 hours of giving birth, and asked to wear them continually on both breasts when they weren’t feeding. Their effectiveness was measured, on the third and seventh days of wearing them, by asking the women to rate the levels of pain they experienced whilst they were breastfeeding, and in the time in between feeds. The scores, displayed in a rather unorthodox graph (where the between and during feed measures are inexplicably joined together with a line), appear to show that the dressings caused pain levels to gradually decline.

Of course, the fact that pain scores are lower on day 7 than day 3 does not necessarily mean the dressings are effective – the chances are, this would happen anyway. To demonstrate that the dressings cause the ratings to go down more quickly than usual, the paper Ziemer et al, 1990, is cited as evidence that without treatment it can take up to 12 days for nipple pain to improve. I have read this paper, and am a little surprised at the way the results have been interpreted: it actually reports that for the majority of women, nipple pain peaks on day 3, and declines thereafter1. If we assume that the ‘1990’ in the main body of text was in fact an error (there is no Ziemer et al, 1990, in the references at the end) and they actually meant to say Ziemer et al, 1995 (which is listed) the citation becomes even less appropriate. I have read this paper as well, and can tell you that the study that it reports ended at 7 days, and is therefore unable to say anything about nipple pain at 12 days2. There are numerous other studies not mentioned in the article that show that mean pain scores start to decline significantly within – who’d have thought? – 7 days of giving birth3.

The article concludes by saying:

The dressings’ moist wound healing properties were an aid in reducing pain and promoting nipple healing, without an increased risk of infection.

The observant among you will have spotted that neither wounds nor infections were monitored, so this claim is, of course, completely unfounded. It may also be wrong: research that has examined using hydrogel in a controlled setting reports that it may in fact delay wound healing and make mothers more vulnerable to infection4. Unsubstantiated or inaccurate statements about the effectiveness of a product are perhaps to be expected from a company trying to sell it. What is truly frustrating about this item of pseudo-science, however, is that it is endorsed by a midwife, lending it legitimacy. When women start breastfeeding they are often feeling stressed and vulnerable. If they can’t rely on health professionals to give them accurate, unbiased advice at this time, then it’s a pretty depressing state of affairs.

  1. West J Nurs Res. 1990 Dec;12(6):732-43; discussion 743-4.
  2. Nurs Res. 1995 Nov-Dec;44(6):347-51
  3. J Obstet Gynecol Neonatal Nurs. 2005 Jul-Aug;34(4):428-37.
  4. Arch Pediatr Adolesc Med. 1998 Nov;152(11):1077-82.

Expressing at work and leaving bodily fluids in the communal fridge

man-opening-refrigeratorWhen C was 6 months old, I had to go back to work. Although I was returning full time (a part time position in my job would mean working full time for a lower salary), I was able to spend two days a week working from home. C would go to nursery while I was in the office, and I would juggle her and my job the rest of the time. (I say ‘the rest of the time’ rather than ‘the other two days’ as this kind of arrangement inevitably spills over into evenings and weekends.)

Her tender age meant that milk was still her main source of nutrition, and I quickly realised I was faced with a dilemma: express milk at work, or switch to formula during the day. If I didn’t pump in the office, my supply could drop to the extent that I’d struggle to feed her myself on the days I was a home, and I’d also find it hard to express enough milk to give her for nursery.

I appreciated that pumping at work wasn’t necessarily an easy option, however. The most pressing concern was the location – where on earth was I going to do it? I didn’t really fancy a toilet or shower cubicle, and I couldn’t think of any obvious alternatives. I was aware that recent legislation requires employers to provide a suitable space for nursing mothers to express, but I seriously doubted that this had been tested in my (predominantly male) workplace before. Although I was right about this, it turned out that I needn’t have worried. The head of admin had breastfed herself, and was completely sympathetic to my predicament. Admittedly, she had to think for quite a while before she came up with what was basically a broom cupboard, but as it was a lockable broom cupboard, I wasn’t going to complain.

So far, I’ve been managing to express milk virtually every day I’ve been at work, although scuttling in and out of the pump cupboard makes me somewhat self-conscious, as there is no obvious reason why I would want to spend 20 minutes in there every lunchtime. I question myself regularly about why I’m so worried about being ‘caught’ going in there, and have come to the conclusion that it’s basically because I don’t want to encourage anyone at work to think about my boobs, especially not in the inescapably undignified process of being milked. I don’t mind people knowing I breastfeed C, but I’d rather not have to explain about the pump.

Storing the milk therefore requires a certain amount of nonchalance. Whilst my colleagues are all liberal, intelligent people, I’m not really inclined to advertise the fact that I’m keeping my bodily fluids in the communal food storage area. Instead, I simply walk in each afternoon avoiding eye-contact and put an odd-looking package directly in the refrigerator. (To disguise the bottle, I’ve ended up wrapping it in several layers of plastic grocery bags, and although this does effectively obscure its appearance, it also looks rather strange.) Whether anyone has guessed what I’m doing I don’t know, but as yet, they’ve been too polite to ask.

Should ‘moist wound healing’ principles be applied to cracked nipples?

pot-of-vaselineMaintaining a slightly damp, rather than dry, environment under a dressing has been shown in many studies to help wounds heal faster. Moisture prevents a scab from forming, which allows new epithelium cells to move across the surface of the wound more quickly, and reduces the time it takes it to close1.

As the technique appears to improve the healing rates of a range of skin lesions2, it has been suggested that its benefits may extend to cracked nipples3, and there are now several off-the-shelf creams and dressings that claim to maintain a moist environment, and thus help the healing process. The inference is not, at first glance, unreasonable – if moisture helps skin to regenerate more quickly, then it may well help injured nipples to recover too. It is important to remember, however, that nipples are subject to a unique set of circumstances when a mother is breastfeeding, so it is also quite possible that the application of the technique might not be appropriate. Is there any scientific evidence that applying moist wound healing principles can aid the recovery of cracked or injured nipples?

In a study comparing dressings made from hydrogel with lanolin (both classified by the Breastfeeding Network as having ‘moist wound healing’ properties)4, 106 mothers were allocated at random to one of two groups: the first was given hydrogel dressings to use between feeds; the second was given lanolin cream. Mothers started using the treatments within 24 hours of giving birth, and their effectiveness was assessed via telephone interviews 3, 4 or 5, 7, 10 and 12 days later. The researchers found mothers reported significantly lower pain scores (a difference of just under 1 point, on a scale of 1-5) in the hydrogel group on days 10 and 12.

There were a couple of problems with this study (actually, there were several, but I’ll limit it to the major ones). Firstly, there was no baseline group of mothers not applying anything to their nipples, so it is not possible to say whether either treatment was better than simply leaving nipples alone. A second issue is that the people conducting the interview were aware, when they spoke to the participants, which treatment they were receiving. The researchers claim that to have conducted the study blind would have been ‘impossible’, an unsubstantiated and somewhat odd statement, as it would appear to be completely possible to interview a mother over the phone without knowing what she had on her nipples. Knowledge of the treatment group in this type of study is a problem if there is any chance that the researcher may have a bias towards a particular treatment, as they may subconsciously influence the patients’ responses. It may be worth mentioning at this point that the research was funded by Tyco, the manufacturers of the dressings.

These criticisms are, however, a digression. The main thing to note about this research is that it did not test whether the dressings actually helped wounds to heal. Although moist wound healing is touted in the introduction as the ‘science bit’ justifying the use of the dressings, it is not mentioned anywhere in the procedure or the results.

A hospital-funded study comparing hydrogel and lanolin – this time documenting the impact that the treatments had on bleeding and cracked nipples – did not find the dressings to be quite so effective5. Researchers who were blind to the treatment group rated nipples as healing significantly better when women used lanolin with breast shells, rather than hydrogel dressings. Self-reported measures of pain were also significantly lower in the lanolin group. A final point worth mentioning is that the study was halted early, due to a third of the 21 women in the hydrogel dressing group developing an infection.

Although this study compared two treatments, it is again compromised by the lack of a proper control group. We can see that lanolin appears to result in improved healing and lower pain scores when it is compared with hydrogel, but we still do not have any evidence that moist wound healing techniques are useful for treating injured nipples when breastfeeding – to ascertain this requires a control group where mothers keep their nipples dry.

So far, there appear to be only two studies that have looked at this issue. An experiment published in 1995 examined whether using a polyethylene adhesive dressing had any effect on the development of nipple redness, fissures and pain6. 50 mothers took part in the study, using a dressing on one nipple, and leaving the other untreated. Although the mothers reported less pain when feeding with the treated nipples, the researchers caution that this may simply have been because of the ‘Hawthorne Effect’ (the mere fact there is an intervention is enough to cause an improvement.) The dressings made no difference to the development or healing of fissures or redness, as reported by observers blind to the treatment group. 16% of the participants dropped out due to finding the dressings uncomfortable, and 66% said they found it uncomfortable to remove them – something they had to do before every feed.

A more recent study looked specifically at the effect of lanolin on the healing of nipple fissures7. 225 women, all with fissures, were randomly allocated to one of three groups: in the first group mothers applied lanolin 3 times a day; in the second they applied breast milk after each feed; in the third they applied nothing. The appearance of their nipples was assessed 3, 5, 7 and 10 days after starting the treatment by researchers who did not know which group the mothers were assigned to. There was no significant difference in healing time between the breast milk and no-treatment groups. The nipples of the women using lanolin, however, took significantly longer to heal (45% of this group took longer than 7 days, as opposed to 32% of the milk group, and 25% of the no-treatment group).

There is another area of research, which does not examine the use of moist wound healing directly, but is still relevant to the debate. Broken skin makes nipples vulnerable to infection8, which may mean there is an additional problem with keeping nipples damp, rather than dry: organisms like thrush are known to thrive in warm, moist environments9.

Given the possible risk of infection, and the evidence that maintaining a moist environment around cracked nipples may potentially delay the healing process, it seems to unwise to recommend the application of the products described above to mothers with cracked or fissured nipples. In spite of this, they continue to be promoted by both commercial companies and health professionals on scientific grounds. Until evidence that genuinely supports its use is found, presenting moist wound healing to mothers as a clinically tested treatment is at best misguided, and at worst dishonest.

  1. Nature. 1962 Jan 20;193:293-4.
  2. Br J Nurs. 2008 Aug 14-Sep 10;17(15):S4, S6, S8 passim.
  3. J Hum Lact. 1997 Dec;13(4):313-8.
  4. J Obstet Gynecol Neonatal Nurs. 2003 Jul-Aug;32(4):486-94.
  5. Arch Pediatr Adolesc Med. 1998 Nov;152(11):1077-82.
  6. Nurs Res. 1995 Nov-Dec;44(6):347-51
  7. Saudi Med J. 2005 Aug;26(8):1231-4
  8. J Hum Lact. 1991 Dec;7(4):177-81.
  9. Hum Lact. 1999 Dec;15(4):281-8.
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