Not enough milk? The “symptoms” you don’t need to worry about.

glass of milkA huge proportion of women worry that they aren’t satisfying their babies through breastfeeding alone, and many give up as a result. Much of the time, however, they are worrying about nothing. Although the precise relationship between perceived and actual milk supply isn’t well researched (see insufficient milk: all in the mind?), it is certainly the case that many of the “symptoms” that women think indicate they aren’t producing enough milk are actually completely normal, and can in fact be indicators that breastfeeding is going well.

In an article for Australian Family Physician journal, Dr Lisa Amir summarizes the common misconceptions of low supply. They include your breasts feeling softer, your baby taking less time to feed or feeding more frequently, your baby seeming unsettled or settling better on formula, and your baby’s growth appearing to slow down after three months1. In the absence of any genuine indicators of ill health, none of the above are a cause for concern, yet they perturb many mothers to the extent that they stop breastfeeding. Why do mothers interpret these commonplace occurrences as signs that their milk production is diminishing, and what actually causes them? The sections below address each ‘symptom’ in turn, outlining why they can be misconstrued as a problem with milk supply, and explaining what actually causes them.

•    Your breasts feel softer

After the problems with engorgement that can occur in the post-birth period, it should come as a relief when breasts go back to a softer, more normal consistency. In reality, it can be somewhat unnerving. If you’re used to rapidly filling up with milk, any decline in this can give the impression of a dwindling supply. In fact, your breasts are simply adjusting to maximize their efficiency, by producing as much milk as your baby needs, but not going overboard – an important process, given how energy intensive it is to produce milk. Initially, production is controlled by hormones that are released after giving birth, causing a significant amount of milk to appear regardless of whether a woman intends to breastfeed. Within a few days, however, the amount produced starts to be determined by the amount of milk that your baby takes at a feed2. The quantity of milk required by your baby increases rapidly to start with, but by the end of the first month it has stabilized, and your production becomes fine-tuned too, so you can supply your baby with exactly what she requires, without wasting energy by producing too much3. This isn’t to say you can’t make more if necessary, but simply that you won’t do it unless the demand is there.

•    Your baby takes less time to feed

Whilst the amount of milk a baby has at each feed remains relatively consistent as he gets older, the speed at which he takes it on board increases. A five month old baby sucks more frequently and ingests more milk with each suck than a two-month old, meaning that he can get through a meal much faster4. Although this gives the impression that he isn’t getting as much milk, you can be reassured he is – he’s simply getting it in a shorter time.

•    Your baby is unsettled, or seems to settle better on formula

The research into colic, crying and the type of food a baby receives presents a confusing picture. Some studies show babies sleep longer if they are breastfed5, while others say formula fed infants are more settled6. One problem that frequently arises with the research in this area is that feeding method is confounded with style of care-giving, and cross cultural studies indicate that the the latter might have a much greater impact on how irritable babies are than the former5. The main thing to remember is that there are many factors affecting how much your baby cries: if you are feeding on demand, a problem with your milk supply is unlikely to be one of them.

•    Your baby feeds more often

A long term study in Sweden has shown that the number of feeds a baby takes in a day can vary by a huge amount, both from baby to baby, and for the same baby over time7. A change in feeding frequency is not unusual, and is not associated with a problem with your milk supply.

•    Your baby’s growth slows after three months

What if your baby has been gaining weight steadily, and then suddenly starts to falter?  The amount of weight babies put on may vary over time for many reasons, but an apparent slow-down from around three months should pretty much be expected. Although the new WHO growth charts were published in 2006, many health care providers (including my own) still aren’t using them, so your baby’s growth is being compared with that of formula fed infants. The really important thing to remember in this situation is that it is actually the breastfed babies’ pattern of weight gain that is considered desirable, so formula fed infants whose growth curve continues to climb are actually gaining too much weight. Or at least this is what the WHO states – presumably the rest of the medical profession will catch up in the next few years.

The issues discussed above frequently cause mothers to worry that they aren’t producing enough milk when in reality their supply is absolutely fine. A baby may cry, fuss or feed more frequently because she is hungry, but this does not mean that her mother is unable to provide her with sufficient milk. The efficient nature of milk production means that if a baby indicates that he needs more milk by taking more at a feed, then the breasts will increase production as required.

The only time to worry is if your baby appears physically ill. If her growth has genuinely stalled, or she is continually tired, weak and listless, there may be a problem: if you’re in any doubt, consult a professional. Just keep in mind that any other ‘symptoms’ of low supply are probably nothing of the sort: as long as your baby is healthy, you almost certainly have nothing to worry about.

  1. Aust Fam Physician. 2006 Sep;35(9):686-9.
  2. Exp Physiol. 1993 Mar;78(2):209-20
  3. J Midwifery Womens Health. 2007 Nov-Dec;52(6):564-70.
  4. J Reprod Fertil. 1999 Mar;115(2):193-200.
  5. Early Hum Dev. 2000 May;58(2):133-40.
  6. Early Hum Dev. 1998 Nov;53(1):9-18.
  7. Acta Paediatr. 1999 Feb;88(2):203-11.

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.