You’ll return to your pre-pregnancy cup size a year after giving birth… even if you’re still breastfeeding

bra and pants

For many women, an increase in cup size as breasts get ready for providing food is one of the first signs of pregnancy. After giving birth, they expand even further as they fill up with milk, but even after a feed, they remain bigger than they were previously, due to the increase in breast tissue required for milk production.

If you continue to breastfeed after solids have been introduced and cut down gradually, your breasts will slowly decrease in size, until you get to the point where you fit back into your old bras. At this point, you’d be forgiven for thinking they can’t possibly be providing your baby with much sustenance, but in fact they are probably doing more than you think. An intriguing article published in Experimental Physiology shows that whilst breast size is related to to the amount of milk produced for the first 12 months of breastfeeding, after this point breasts return to and stay at their pre-pregnancy size, even if they are still manufacturing milk1.

The study followed 8 mothers who breastfed exclusively for 6 months, and weaned after 18 months. Milk production over a 24 hour period was measured by test-weighing the mother2 and breast volume (their actual size minus the amount of milk produced) was calculated using a special ‘Computerized Breast Measurement’ system3 at 1, 2, 4 and 6 months after giving birth, and then at three monthly intervals until weaning.

Milk production – and breast volume – remained constant for the first 6 months, and both started to decline after this point as other food was introduced. By 15 months, however, breast volume had reduced to the level it was before the women gave birth, and remained at this point from then on even though the mothers were still producing on average 200g of milk a day. When the mothers weaned their babies completely, there was no significant further reduction in breast size.

The authors state that this occurs because breasts become able to make milk more efficiently: although an increase in breast tissue is necessary to initiate and sustain a high level of milk production, when it naturally declines as milk output falls, the remaining tissue is still able to produce a significant amount of milk.

For any mothers who are nursing past the 12 month mark but sceptical that their breasts are still up to the job, this will make interesting reading. Even though it may sometimes seem as if you don’t have anything left for milk production, the chances are you’re more than capable.

  1. Exp Physiol. 1999 Mar;84(2):435-47.
  2. J Pediatr Gastroenterol Nutr. 1987 Sep-Oct;6(5):758-63.
  3. Exp Physiol. 1992 Jan;77(1):79-87.

Nipple shields and milk yields: an update

In a previous post I questioned the received wisdom that using nipple shields will have a negative impact on your ability to nurse your baby (see nipple shields: always a bad thing?). The post challenged one of the main criticisms made of shields — that they slow milk transfer and may therefore mean your baby is inadequately nourished — on the grounds that most of the studies demonstrating this were conducted a long time ago, and more recent research indicates that this problem does not exist for modern shields1.

The researchers who conducted the study in question concluded that nipple shields do not affect the amount of milk babies consumed in a feed by weighing before them before and after they nursed: when a mother was using a shield, the amount by which her baby had increased in weight at the end of the feed was roughly the same as when she was breastfeeding directly. Whilst this result looks positive for nipple shields, ‘test-weighing’ babies in this way is not without its critics, so one could argue that concluding nipple shields have no effect on milk consumption based solely on this evidence is a little premature.

Since writing the post, a follow-up study has been published, this time looking at the relationship between shield use and infant weight gain over a much longer period2. 54 mothers who used a nipple shield provided by a nurse or lactation consultant in the period just after the birth of their babies were recruited for the study, and completed interviews when their babies were 2 weeks, 1 month and 2 months old. Over time, the proportion of mothers using shields diminished (at 2 weeks,  69% of the mothers were still doing it, at 1 month 48%, and at 2 months 33%) and at each stage the responses of women who were still using the shields were compared with those who weren’t.

The main aim of the study was to determine whether nipple shields had a negative impact on weight gain — if babies whose mothers were still using shields grew more slowly than those whose mothers had stopped, then this could be taken as an indication that medium to long term use of shields was causing a real problem. Happily, there was no difference between the groups: whether a mother used a shield made no difference to her baby’s pattern of weight gain.

There were a few complaints about nipple shields: 8 women thought they caused nipple soreness; 2 found them messy; 2 found them inconvenient and 3 had problems with them falling off. In spite of this, 90% of the mothers in the study said that using the shield was a positive experience, and 67% felt it helped prevent them from giving up breastfeeding.

If you are a mother who relies on a nipple shield to breastfeed, these results make reassuring reading. Although shields appeared to cause difficulties for a few women, these were generally minor, and crucially they concerned practical issues, not the health of their babies. As most women felt that shields helped to prolong the period that they were able to breastfeed, this study ultimately supports the view they could be an important intervention for mothers who are having problems, rather than something that will make them worse.

  1. J Obstet Gynecol Neonatal Nurs. 2006 Mar-Apr;35(2):265-72.
  2. J Clin Nurs. 2009 Nov;18(21):2949-55.

Can breast milk cure an eye infection?

eyeOne of the many healing properties attributed to breast milk is the ability to cure eye infections such as ‘pink eye’ — conjunctivitis — or ‘sticky eye’ — a gooey discharge that often accompanies conjunctival inflammation. Conjunctivitis is a common condition that rarely requires treatment, usually clearing up by itself within a week or two. For newborns, however, it can occasionally be quite serious, so ensuring it is properly treated is very important. For everyone else, it can be irritating and unpleasant, so any way of reducing the length of the infection is naturally welcome. Can breast milk really provide any relief?

A study in a hospital in New Delhi, India, examined the effect that routinely applying colostrum to babies’ eyes had on the likelihood of them developing an eye infection1. On one hospital wing, mothers were asked to put a drop of colostrum in their babies’ eyes three times a day; on another wing, mothers were asked not to apply anything. The infection rate was much lower in the babies who received colostrum: only 3 out of 51 babies in this group (6%) developed an infection, compared to 26 out of 72 in the control group (35%).

At first glance, this seems like a convincing result for colostrum, but a closer examination of the figures indicates this isn’t necessarily the case. The normal neonatal eye infection rate recorded at the hospital was just over 5% – roughly the same as the one recorded in the colostrum group. Rather than infection rates going down in the babies who received colostrum, it seems they went up – considerably – in those who didn’t. This may have occurred because the normal practice of wiping eyes with a sterile swab just after birth was abandoned during the study. Fewer babies in the study group may have got infections simply because their eyes were rinsed, not necessarily because it was with colostrum.

There is other evidence that breast milk could help ease the symptoms of conjunctivitis, however: in vitro tests show that colostrum, and to a much lesser extent mature breast milk, can potentially combat some of the bacteria known to cause neonatal eye infections2,3, and another study provides evidence that it does seem to be an effective treatment for eye infections in young babies4. At a hospital in Spain, babies diagnosed with neonatal sticky eye were treated either with antibiotics or breast milk. Babies treated with breast milk generally recovered much faster: 26 out of 45 (57%) of those receiving milk had recovered after 30 days, compared with 3 out of 20 (15%) of those receiving antibiotics. Whilst this does not provide conclusive evidence that breast milk is the optimal treatment for eye infections in newborns, the study’s results were deemed sufficiently encouraging to switch from antibiotic drops to breast milk at the hospital where it took place.

So does this limited evidence that breast milk can treat some neonatal eye infections mean it can be used to treat infections in older children, or even adults? Whether breast milk would have a beneficial effect is not clear: its antibacterial properties mean that it may help to clear up an infection caused by certain types of bacteria, but not necessarily one resulting from an allergy or a virus. Having said this, there is, of course, no harm in trying the breast milk option. If you’re currently nursing, it’s simple and free, and whilst it may not get rid of the symptoms, it almost certainly won’t make them any worse.

  1. J Trop Pediatr. 1982 Feb;28(1):35-7.
  2. J Trop Pediatr. 1996 Dec;42(6):327-9.
  3. J Reprod Immunol. 1998 Jul;38(2):155-67.
  4. J Trop Pediatr. 2007 Feb;53(1):68-9.

Breastfeeding and thrush: preventing reinfection

microwaveA bout of thrush when you are breastfeeding can be problematic in many ways. Not only are candida yeast infections often painful and tricky to diagnose, but they can also be remarkably persistent: antifungal medication may appear to alleviate the problem, but not eradicate it completely, or it may clear up one episode of thrush, only for another to appear a short time later.

One reason for the longevity of nipple thrush is the high potential for re-infection. Medication can keep yeast at bay while you are using it, but as soon you stop you become vulnerable to attack again. The most potent reservoir for candida species that your nipple comes into contact with is your baby’s mouth (even symptom-free babies are often carriers1), so ensuring this is treated with an antifungal at the same time as your nipples is essential for effectively combating thrush. It is not the only place spores can gather, however – hands and other objects can easily become colonized too, and whilst washing something that has only been in contact with candida spores for a short time can usually get rid of them2, certain objects are able to host thrush for quite a long period.

Towels and clothing are among the surfaces that are at high risk of habouring candida. A study looking at the length of time fungal spores could exist on a variety of fabrics used in hospitals found that candida survived for an average of 5 days after inoculation, and lasted longer on synthetic materials (polyethylene, polyurethane, spandex, polyester) than cotton or fabrics that were a mixture of natural and synthetic fibers3. Washing fabric can eradicate thrush, but it may need to be at a high temperature: one experiment found that candida spores could survive the wash at 50 degrees Celsius, but not 704 (although it should be noted that this research was conducted some time ago, and modern detergents may be more effective at lower temperatures).

The use of a pacifier is significantly associated with oral thrush in babies, indicating that dummies or soothers may also provide a friendly environment for candida spores1. A study examining the microorganisms prevalent on the surface of pacifiers showed that this was indeed the case. Like teeth and dentures, pacifiers can develop biofilms that play host to a complex array of microorganisms including numerous bacteria and funghi5. Biofilms are pretty persistent: simply ‘sterilizing’ with boiling water will not remove them5,6. It is not impossible to get rid of them, however, and in fact an effective means of doing this can be found in most domestic kitchens. When candida spores are subjected to microwaves for a sufficient length of time, their cell membranes are irreparably damaged, rendering them ‘inactivated’6. Three minutes immersed in water in a 650W microwave is able to eradicate candida from dentures7, and the chances are this is also an effective way of sterilizing pacifiers.

The best way of treating thrush is to take a sufficient course of antifungal medication, but to prevent it returning it is also a good idea to ensure that anything coming into close contact with nipples or mouths (such as towels or pacifiers) is kept free of rogue candida spores. Whilst washing hands in soapy water will generally decontaminate them, this is not necessarily the case for fabric or pacifiers, which can provide a home to yeast spores for some time, even after they have been superficially cleaned. To get rid of candida for good, there are two options: a hot wash or session in a microwave; or throwing everything out and starting again. Whilst the second option may be tempting, it may also prove rather expensive – fortunately the first option should do the job just as well.

  1. J Oral Pathol Med. 1995 Sep;24(8):361-4.
  2. Eur J Clin Microbiol Infect Dis. 1994 Jul;13(7):590-5.
  3. Clin Microbiol. 2001 Sep;39(9):3360-1.
  4. Br J Vener Dis. 1984 Aug;60(4):277.
  5. Nurs Health Sci. 2006 Dec;8(4):216-23.
  6. Mycoses. 2007 Mar;50(2):140-7.
  7. J Dent. 2009 Sep;37(9):666-72.

Breastfeeding and thrush: what are the treatment options?

medicineThe symptoms associated with thrush (a candida yeast infection) in breastfeeding women vary. Some have red or shiny nipples, fissures or flaking skin, others exhibit no visible signs at all1. There is one symptom, however, that is reported almost universally: pain. It is usually described ‘in the strongest terms, with words such as “agonizing” or “excruciating” often being used’, and can occur throughout a feed and continue for sometime afterwards2. Faced with this level of discomfort, it is not surprising that many mothers diagnosed with thrush feel unable to continue breastfeeding3,4.

This shouldn’t be the case, of course; fungal infections are highly treatable, so contracting one need not automatically spell the end of breastfeeding. Unfortunately, getting medication for this type of thrush isn’t always straightforward, particularly if you are unlucky enough to have an unsympathetic doctor (see breastfeeding and thrush: it’s complicated). Health professionals who are reluctant to diagnose thrush, are naturally hesitant to prescribe for it, so some mothers may be left suffering unnecessarily, or given the wrong medication, such as antibiotics, which may actually make the condition worse2.

An additional problem is that the evidence base for treating breastfeeding yeast infections is sorely lacking. Although there are many antifungal drugs available, there have yet to be any controlled clinical trials examining their effectiveness for treating a candida infection of the breast. The difficulty confirming a diagnosis may be one reason for the lack of trials: milk and skin cultures aren’t always reliable, so it could be difficult to know whether a treatment failed because the drug was ineffective, or because the symptoms weren’t actually caused by candida. Alternatively, it may be because this research simply isn’t viewed as a priority: if an infection is caused by candida, then it should clear up eventually providing enough antifungals are thrown at it5. This ignores the possibility that the unique environment breasts are subject to during nursing may impact on the effectiveness of a treatment, but at present it’s the most ‘scientific’ approach we have.

Case studies and anecdotal information sources (which generally consist of health professionals giving opinions based on their clinical experience) also offer theories about the best way of treating thrush. A traditional medication for nipple thrush recommended on numerous breastfeeding websites (albeit mostly in articles written by the same person) is gentian violet, a purple ointment that can be applied to both nipples and babies’ mouths. Although there are no controlled clinical trials supporting its use for nipple thrush, it is known to be an effective antifungal, and there is anecdotal evidence it can be helpful for breastfeeding women2. Gentian violet does have its drawbacks, however. A minor issue is that it is messy (it is used as a dye); a more serious concern is that it can cause skin irritation6 and may be carcinogenic7, and as such it is not available for this purpose in the UK.

Due to the lack of clinical research in this area, there is no definitive list of drugs that are suitable for treating thrush in breastfeeding women, so theoretically any medication that is antifungal and unlikely to cause problems for a nursing baby could be prescribed. Common topical treatments include miconazole and clotrimazole, which are usually supplied in creams or powders. These are not advised for internal use, so it is generally recommended that they are removed before breastfeeding, although this is due to the ingredients in the base of the medication, rather than the antifungals themselves (both can be used to treat oral thrush if they are supplied in the appropriate preparation). Nystatin can also be applied topically to the nipples and is usually supplied in a formulation that does not need to be washed off. It is often used for treating thrush in babies’ mouths, and as such is often the first medication suggested for treating mothers too5.

Anecdotal evidence suggests that topical treatments aren’t always effective, however, and thrush can be treated more reliably with fluconazole5,8 (a clinical study suggests that this is the case for oral thrush too9.) Unlike creams and ointments that only treat the skin where they are applied, fluconazole has the additional advantage of being taken internally, providing a blanket assault on candida wherever the site of infection.

Although organizations like the Breastfeeding Network and the NHS suggest that fluconazole is a good treatment for mothers who appear to be suffering from persistent thrush, it can pass into milk in small amounts, and is not currently licensed for use when breastfeeding. As it can be safely given to newborns, this is not a great concern. The fact that the breastfeeding box isn’t officially ticked can make doctors cautious, however, leaving some women without potentially important medication. The opinion that fluconazole shouldn’t be given to breastfeeding women unless it is part of a controlled clinical trial can also be found in the scientific literature10, and while this idea is reasonable in theory, until someone actually gets round to running the trial, it isn’t so great for those women experiencing ‘intolerable and incredible pain’ that may be due to thrush11.

At present, there isn’t any concrete evidence that fluconazole (or indeed, any medication) is suitable for treating yeast infections in breastfeeding women, because there haven’t been any controlled clinical trials looking at its use in this situation. Until such trials are conducted, there are a couple of options. One is to deny women antifungal medication on the grounds that there is no proof it works. An alternative – supported by numerous breastfeeding organizations – is to advise women with suspected thrush to take fluconazole orally, to treat nipples topically and ensure their babies’ mouths are treated too, in the hope of alleviating symptoms. Proper research in this area would naturally be a great step forward, but until it occurs (if it ever does), it seems only fair to offer women suffering very painful symptoms at least a chance at respite, particularly if it enables them to continue breastfeeding.

  1. J Hum Lact. 2004 Aug;20(3):288-95.
  2. Aust N Z J Obstet Gynaecol. 1991 Nov;31(4):378-80.
  3. J Obstet Gynecol Neonatal Nurs. 2005 Jan-Feb;34(1):37-45.
  4. Clin Pediatr (Phila). 2001 Sep;40(9):503-6.
  5. J Hum Lact. 1999 Dec;15(4):281-8.
  6. J Hum Lact. 1990 Dec;6(4):178-80.
  7. Fundam Appl Toxicol. 1985 Oct;5(5):902-12.
  8. J Hum Lact. 2002 May;18(2):168-71.
  9. Pediatr Infect Dis J. 2002 Dec;21(12):1165-7.
  10. Breast. 2002 Feb;11(1):88-90
  11. J Hum Lact. 1997 Dec;13(4):307-11.