Hydrogel dressings in the British Journal of Midwifery

nurse-with-clipboardA few weeks ago, I talked about a ‘clinical case study’ posted on a medical supply manufacturer’s website, apparently demonstrating the benefits of using hydrogel dressings when breastfeeding. Unfortunately, the study was poorly designed, and therefore unable to provide support for its considerable claims. It showed, at best, that the dressings did not appear to cause any major problems for a small group of women.

Since then, the dressings have been tested in a larger, controlled study, published in the British Journal of Midwifery1. The article, which describes the dressings as ‘designed to physically protect wounds while maintaining a moist environment,’ concludes that, ‘the dressings can reduce the pain and discomfort associated with nipple excoriation.’ This rhetoric sounds pretty impressive – but does it accurately reflect the strength of the evidence?

On the surface, the study appears to be well designed and reported: 64 mothers were randomly assigned to either the experimental group (wearing dressings between feeds) or the control group (rubbing breast milk on the nipple after a feed), and self-reported pain scores were recorded in interviews 5 times over 14 days. If you read the article carefully, however, a number of inconsistencies become apparent. The abstract and ‘study objectives’ sections say that the aim of the study was to compare the dressings with ‘breastmilk expression and patient education (control group).’ We learn later that in fact both groups received education. The study hypothesis was that, ‘the dressings may reduce nipple pain and excoriation.’ While excoriation (skin wounding/abrasion) is mentioned several times, it was never actually measured – or if it was, the results are not reported.

That the dressings resulted in ‘a considerable reduction in pain’ is highlighted in a special ‘key points’ box. In fact, pain was significantly lower in the dressings group on only one occasion – day 12. The results section states that the average score for the dressings group on this day was 1.3, compared to 2.0 in the control group, and refers you to a graph showing how the scores declined over time. Confusingly, this graph shows the control group score on day 12 not as 2.0, but as 1.4. Clearly, one set of figures is wrong. Given the gradual downward trend of both sets of scores, it would be pretty odd if a pain score went from 1.4 two days previously, to 2.0 (the highest score, recorded at the start of the study), and back down to 1.4 two days later. It seems more plausible that the figures are misreported in the text, and that the statistical tests were in fact conducted with errroneous data. ‘Comfort scores’ are also reported to be consistently lower in the dressings group, although it is not completely clear what these are. They are not mentioned in the method section, and are described in the results section as ‘acceptance of the treatment’ measured using the 1-5 verbal descriptor pain scale. This is the same scale used to measure the other pain score, and how the two actually differ is not explained. Again, the graph and text do not match. The text says that comfort was recorded on days 3, 5, 10 and 12, but the graph also shows data for this measure on days 7 and 14. Interestingly, days 3, 5, 10 and 12 result in comfort scores of 1.0 for the dressings, whilst 7 and 14 show the scores as 1.2 and 1.4 respectively – is it possible these higher scores were conveniently excluded from the analysis?

There are other examples of sloppiness that call into question the integrity of the research. In the introduction, a paper is cited as saying that nipple pain typically starts to decline by day 12. In fact, the study reported in this paper only lasted 7 days2 (this same error occurs in the ‘clinical case study’ reported on the manufacturers website – one can only assume the authors copied the reference without actually bothering to check it). We are told 11 participants dropped out of the study, but not which group they belonged to (they could all potentially have been using the dressings). It is also not clear why 30 people were ‘randomized’ to the dressings group, and 34 to the control group. Why not have 32 in each? A presentation at the International Lactation Consultants’ Association (ILCA) Conference describing the study in progress stated there were 30 women in each group3; why the control group then increases by 4 (unbalancing the design) is a mystery. This presentation also said that breastfeeding duration was being analyzed. Why is this data not provided?

Given that these less than convincing results are reported with great enthusiasm, you would be forgiven for thinking that this might simply have been a promotional exercise. And that, of course, is precisely what it is. Although it is described as ‘sponsored’ research, and discretely labeled as a ‘product focus’, it is not a study that would ever have been published with a negative result.

If you ignore the problems with the figures, and simply take the data at face value, it is possible that the dressings may have provided increased ‘comfort’ for some women. The difference between the scores of the two groups is less than a point, however, and could conceivably be down to experimenter bias, as the investigators conducting the study may have been keen to obtain a positive outcome for their sponsor. Even if the effect is genuine, it certainly does not translate into the substantial support for the dressings claimed in the article. The dressings are marketed as having moist wound healing properties, and although these are alluded to frequently, they are never actually tested. Previous research has shown that hydrogel dressings do not help nipple wounds to heal more quickly when women are breastfeeding, and may potentially foster infection4. When you consider it in this context, what initially appears to be genuinely useful research, may in fact be harmful propaganda.

  1. Br J Midwifery. 2004 Apr;12(4):244-248.
  2. Nurs Res. 1995 Nov-Dec;44(6):347-51.
  3. J Hum Lact 2004; 20; 211.
  4. Arch Pediatr Adolesc Med. 1998 Nov;152(11):1077-82.

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.

Peppermint might help prevent early breastfeeding nipple problems

peppermintThere are many substances said to prevent or relieve nipple pain and damage during the early days of breastfeeding, including lanolin, expressed breast milk and water compresses. Unfortunately, none as yet have been found to offer any real improvement over leaving nipples untreated1. Given the prevalence of the problem, however, the search for a preparation that can make early breastfeeding more comfortable continues.

Recent research reported in the International Breastfeeding Journal and Medical Science Monitor finally seems to offer a ray of hope. It suggests that peppermint, in the form of a gel or ointment, could play a role in preventing nipple soreness and injury from appearing in the first place. A team at the Alzahra Teaching Hospital in Iran conducted two studies examining whether peppermint could prevent nipple problems caused by breastfeeding, after noticing its use by women in the Azarbaijan Province, North West of Iran. As peppermint has antibacterial properties and can increase tissue flexibility2 it does have the potential to prevent this kind of injury occurring, but it has not before been properly evaluated in a clinical setting.

In the first study, 196 women were randomly allocated to either the experimental group, where they were asked to apply peppermint water after each feed, or the control group, where they applied expressed breast milk3. Mothers who applied the peppermint water reported significantly less pain on breastfeeding, and had significantly fewer nipple cracks (9% in the peppermint group and 28% in the milk group) than the other mothers. Cracks that occurred in the peppermint group were also less severe than those in the milk group.

The second study evaluated the effectiveness of a peppermint gel in a double blind study4. 216 women were randomly allocated to one of three groups: the first used peppermint gel after each feed; the second used lanolin; and the third used a placebo gel. The peppermint gel was shown to be more effective than both lanolin and the placebo gel at preventing nipple cracks. Women in this group were also more likely to be exclusively breastfeeding at 6 weeks, possibly because they had suffered less discomfort.

Both these studies were large and well designed, and as such offer reasonable evidence that peppermint may indeed help to prevent the nipple pain and trauma that can occur when women start to breastfeed. These results alone, however, do not constitute conclusive proof that peppermint is a panacea for nipple problems. The main issue is that both experiments were carried out by the same research group, in a part of the world where peppermint is regularly used as a nipple treatment. In the first study women knew they were applying peppermint water, and this may have affected their perceived levels of pain. These mothers were also found to nurse their babies more frequently and for longer periods than those using milk. The authors suggest this may be due to the lower pain levels in this group, but the possibility that the more frequent feeding somehow reduced pain and trauma cannot be ruled out.

In the second study, both the mothers themselves and the researchers classifying the severity of nipple cracks were unaware which type of gel they were applying, reducing the chance that the results were due to a placebo effect. In this experiment, however, there was no true baseline (where nipples were left untreated) against which to compare the peppermint gel. It was better at preventing cracks than the placebo gel (which was the same preparation, just without the peppermint), but we can’t be sure that the gel didn’t make it worse, and the peppermint simply helped to ease the problems caused by the gel.

Despite these shortcomings, this research does provide a strong indication that peppermint may have the potential to protect mothers against nipple soreness and injury. Peppermint has medicinal qualities that suggest it might be helpful in this context, and it is likely to be a reasonably safe and practical treatment, as it is not harmful to babies when consumed in small quantities. Whether future research can replicate these results is yet unknown, but if it can, then an effective preventative measure for nipple problems may finally be on the horizon.

  1. J Obstet Gynecol Neonatal Nurs. 2005 Jul-Aug;34(4):428-37.
  2. Fitoterapia. 2006 Jun;77(4):279-85.
  3. Int Breastfeed J. 2007 Apr 19;2:7
  4. Med Sci Monit. 2007 Sep;13(9):CR406-411

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.

Nipple solutions 3: pumping

bottleIn addition to using a nipple shield, both the health visitor and the NCT helpline lady suggested I try expressing milk and feeding it from a bottle, to give my nipples a bit of a rest. C’s response to the shield was not encouraging, so using a breast pump was really the only option I had left if I wanted to carry on. So far I’d just about been able to put up with the pain: if I gritted my teeth through the initial agony, the remainder of the feed was just about bearable. The sight of my nipples, however, was really quite perturbing. The open wound on the outside edge of one was so deep it looked as if the nipple were in danger of detaching. The psychological effects of seeing this type of damage were considerably worse than the pain. I could only assume it was getting worse with each feed, and therefore that I was mutilating myself further.

Despite the obvious arguments for using a pump, and possessing one that was bought before C even arrived, it took me another couple of days to get around to using it. I don’t know quite why I was so reticent, but I think it had something to do with feeling guilty and inadequate not being able to get it right on my own. The turning point was speaking to my friend Zara. It turned out that she’d had exactly the same problem – right down to the fissures in the same place – and had pumped to help with the healing. She’d also had the same feelings of guilt and inadequacy, but had come through the other side and said that it made a massive difference. I wasn’t going to get any extra points for prolonging the pain, so I should just get on with it.

Some women find expressing milk easier than others. The key is prompting the letdown reflex – after that getting milk out is reasonably straight forward. Without your baby actually suckling, however, letdown isn’t always that easy to initiate. Looking at a picture of your baby (or indeed your baby herself) is one way of getting the vital oxytocin flowing. The solution for me was pumping from the really mangled left hand side, while C fed from the slightly less injured right hand side. For about four days, I expressed on the left and fed on the right, feeding C the expressed milk in a bottle if she was still hungry.

Using the pump and feeding simultaneously gave me an interesting way to monitor the extent to which the expressing helped. I had the same injury on both sides (albeit not as badly on the right), but only used the pump on one. It definitely provided me with some relief – expressing was much less painful than feeding – and the nipple did heal eventually, but the right side also healed completely, without any intervention. The healing actually occurred slightly faster on the right hand side, although this might be expected, as the injury wasn’t quite so serious. It seemed that the midwife who told me that things would eventually improve of their own accord was right after all. I think the problem for me was caused by the fact that my nipples weren’t quite the right shape initially (for C’s mouth at any rate – I don’t know if it would be different with another baby) and the skin broke so they could be stretched into a better one. Certainly, they now look quite different to how they did originally – pointy where they were once quite flat. When they healed, extra skin grew over the fissures where they’d stretched, rather than the skin knitting together at the point where it was originally joined, providing further evidence that my nipples were simply going through a (very painful!) transitional process.

Although it seems that both nipples would probably have recovered of their own accord if I’d continued feeding C as normal, I would strongly recommend using a pump if your nipples are suffering. It really helps to relieve the pain, and if you plan to bottle feed later on (whether with expressed milk or formula), introducing it early (and continuing regularly) means you should meet less resistance later on. Even if you take into account the constant pump dismantling, sterilizing and constructing, it’s a win-win situation!

Is lanolin cream a waste of money?

ointments_photoGiven the high incidence of nipple pain (it seems most women experience it when they start breastfeeding1), it would be reassuring to know that something can be done to relieve it. At the breastfeeding antenatal class the midwife told us that there is no evidence for the effectiveness of most nipple creams, although there have been studies showing that Lansinoh (commercially available purified lanolin) helps, and this is the one to go for if you have a problem. This view was echoed by two other midwives (one of whom gave me some sachets) and an NCT breastfeeding counsellor. You can read about my experience of using this preparation in the nipple solutions 1 journal post, but suffice to say that it didn’t work for me.

So, what is the scientific evidence for the effectiveness of lanolin? Probably the first thing to mention is that most of the big brand off-the-shelf nipple creams are simply moisturizers, and as the midwife said, there aren’t any published clinical trials supporting their effectiveness. On top of this, most of them aren’t even safe to go in babies’ mouths, so have you have to clean them off first – not ideal. This isn’t the case for Lansinoh – as it is simply purified lanolin, it isn’t a problem if babies swallow it (although this in itself doesn’t mean it’s worth using, of course).

An article looking at various topical treatments for nipple pain reviews several studies testing the effectiveness of lanolin1. When compared with hydrogel dressings (designed to maintain a moist wound healing environment), lanolin does well. In one study, women treated with lanolin reported significantly less nipple pain and were less likely to suffer from infection than those using the dressings. In another, there was no difference in pain relief, but there were still fewer infections in the lanolin group. Evidence that lanolin is a useful treatment? Not necessarily. As neither of these studies had a control group where no treatment was given, all we can tell is that hydrogel dressings are a bad idea. A study looking at the effect of heat treatment (sunshine or heat lamps) suffers from a similar problem. Using lanolin with the heat treatment offered greater pain relief than using the heat treatment alone, but unfortunately there is no way of telling whether this is better than not using any treatment at all.

In fact, the three studies in the review that compared lanolin with a ‘no treatment’ baseline showed it to be no more effective than leaving the nipples alone. There is also evidence that lanolin offers no improvement over rubbing on expressed milk (which is also reported as being pretty useless at reducing pain). The article also reports some preliminary research indicating that glycerin gel is a better treatment for sore nipples than lanolin (although a later study has found no difference between the two2.

Two further studies also deserve a mention. One provides evidence that peppermint gel is better at preventing nipple cracks and pain than lanolin or a placebo gel3. Another shows that in certain circumstances applying lanolin not only offers no improvement, but might actually make things worse4. The study compared using lanolin cream or breast milk with not using a treatment. The results showed that the appearance of nipple wounds (cracks and fissures) was the same in each group. However, the women who applied breast milk or used no topical treatment recovered significantly faster than those using lanolin.

So, it seems you may be better off ignoring the health professionals’ advice to use a lanolin cream. If you want to keep your nipples trauma-free you may want to think about using peppermint gel, or alternatively go for the inexpensive option of not bothering to treat them at all.

  1. J Obstet Gynecol Neonatal Nurs. 2005 Jul-Aug;34(4):428-37.
  2. J Perinat Educ. 2004 Winter;13(1):29-35.
  3. Med Sci Monit. 2007 Sep;13(9):CR406-411
  4. Saudi Med J. 2005 Aug; 26(8):1231-4.
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