Articles published on this blog are my opinion only, and may not necessarily reflect the views of any organisations with which I am associated. Please be aware that articles posted on this blog are not intended as a substitute for professional medical advice. If you have a medical problem relating to breastfeeding, please seek further advice from a Lactation Consultant (IBCLC) or trained Breastfeeding Counsellor.

Sunday, 2 January 2011

The “Breasts Feeling Full = A Good Thing” Myth

When I asked Anne of Dispelling Breastfeeding Myths to produce an article on this topic, the last thing I expected her to say was, "Why don't you try writing one yourself?" Wondering what I could possibly contribute to the blogging world of breastfeeding, I took up her challenge. Anne kindly published the resulting article on Dispelling Breastfeeding Myths; it was then republished by Flintshire Feeders, a Breastfeeding Peer Support Programme in North Wales. A wonderfully supportive and inspiring lady (see for yourself on her facebook page), Anne has encouraged me to start blogging, so brace yourselves!

Here's the article:

Nearly nine years have passed since my first (fairly disastrous) breastfeeding experience. One of the things I recall is feeling a sense of pride because I frequently got a really full feeling in my breasts: I could feel I was producing plenty of milk. I would wait for my breasts to feel full – and, if I’m honest, fairly uncomfortable - before I latched my baby on, believing the full feeling was a good thing: it indicated nature’s bottles were full of milk ready for a feed. So I was understandably confused when I was told my baby’s weight gain was too slow and she was failing to thrive. Lacking proper information and support, the only advice I received to remedy this was to give her formula top-ups, which spelt the end of our breastfeeding relationship.

Thankfully, I have since received far better breastfeeding support, have gone on to successfully breastfeed three subsequent children (two of whom I am still breastfeeding) and have become a LLL breastfeeding peer supporter. Though I now realise that the experience I had with my first baby is not uncommon: I often encounter mothers who, like I did, believe they need to feel full before they feed their baby, and who worry unnecessarily when their breasts no longer feel full.

MYTH: Breasts are like bottles, which empty and need to be refilled. I need to wait for my breasts to fill up before I feed my baby.

FACT: Feeling full isn’t necessarily a good thing. This full feeling means milk is accumulating in your breasts, which tells your body it is making too much milk. This milk isn’t being used by your baby, so your body thinks there is no demand for it, and starts to reduce your milk supply. Frequent removal of milk is key to building and maintaining a good milk supply.

This might seem like crazy, upside-down logic, but it works. For those who are interested, here’s the sciency bit:


FACT: If your breast is full, your milk production is SLOWER.
FACT: If your breast is emptier, your milk production is FASTER.

“Evidence exists that there are two interacting mechanisms regulating the rate of milk synthesis.” 
 ~ van Veldhuizen-Staas 2007

The first mechanism involves Feedback Inhibitor of Lactation (FIL). FIL is a whey protein present in your milk, which is thought to slow milk production in each breast independently when it is full. When milk accumulates in the breast, FIL accumulates in the breast and milk production slows down.

The second mechanism involves prolactin and prolactin receptor sites. Inside your breasts you have milk-making cells (called lactocytes). On the membranes of these milk-making cells are prolactin receptor sites. Prolactin receptor sites behave a bit like locks: they need a key to make them work. This key is called prolactin. Prolactin is “the major milk-stimulating hormone” (West & Marasco 2009, p6) that travels along your bloodstream and temporarily binds to the prolactin receptor sites (the locks), which then sends a message to the milk-making cells to stimulate milk production (a little bit like starting the ignition in your car). It is thought that as the breast fills with milk, the shape of the milk-making cells change, so that prolactin can no longer bind to its receptor sites. This tells your body it is making more prolactin than it really needs, so your prolactin levels drop. Milk synthesis slows, and eventually stops.

Frequent removal of milk is important because:
  • FIL is removed from the breast. This speeds up milk synthesis.
  • Prolactin can bind effectively to prolactin receptor sites on lactocytes, which stimulates more milk production. Your baby’s suckling at the breast actually increases prolactin levels in your blood, which increases milk production. Prolactin levels are highest after frequent feeding “when the breast is most fully drained of milk” (LLL GB 2009) (this is usually at night).

If you didn’t 'get' all that, don’t worry! The most important bit to remember is this:

FACT: If your breast is full, your milk production is SLOWER.
FACT: If your breast is emptier, your milk production is FASTER.

Your body is constantly fine-tuning your milk supply to exactly meet your baby’s needs. This means there may be occasions when your breasts will feel fuller, including:
  • when your milk “comes in” a few days after the birth of your baby. Your body doesn’t yet know how much milk your baby (or babies!) is likely to demand. So your body may simply respond with copious milk production, resulting in an (over)full feeling in your breasts.
  • at certain times over the first few weeks as your body is fine-tuning your milk supply.
As long as you are feeding on demand, the initial overzealous milk production is gradually adjusted and continually regulated to exactly meet your baby’s needs. As your milk supply becomes more efficient, your breasts lose their feeling of (over)fullness and will feel soft most of the time.

MYTH: If my breasts feel empty and my baby still wants to feed and feed and feed, it means something is wrong.

FACT: Feeling empty is actually a positive thing! This empty feeling means your baby is removing milk efficiently from your breasts, which tells your body to make more milk. If your baby wants to continue suckling on a breast that feels empty, this tells your body that your baby is demanding more milk, and so your body starts to increase your milk supply. Allowing unrestricted suckling at the breast is important for helping your milk supply adjust appropriately to your baby’s needs.

Feeling empty does NOT mean you’re not producing enough milk for your baby, or you need to give your breasts a break to allow your milk supply to ‘catch up’.  Feeling empty does NOT mean your milk is too thin or drying up, so there’s no need to supplement with artificial milk or introduce solid foods prematurely.  There is no need to worry about whether your baby is getting enough milk if he/she is gaining weight well and producing plenty of wet and dirty nappies Feeling empty does NOT mean you need to worry that your baby is using you as a dummy or that your baby needs a pacifier.

In fact, there is evidence that supplementing and use of dummies could cause more harm than good: if your baby is sucking on an artificial teat, he is not stimulating your breast, and so the messaging system which tells your body to keep up with his demand for milk is disrupted.

Normal breastfeeding behaviour includes periods when baby needs to feed more frequently, such as:

  • cluster feeding (which often occurs in the evenings),
  • during growth spurts
  • around developmental milestones (such as rolling over or crawling).
Although frustrating and tiring, these periods of increased breastfeeding are absolutely normal.  They soon pass. During these times, your breasts will feel very soft. Although you may notice that your milk flow is slow,this doesn’t mean your milk production is slow!

FACT: If your breast is emptier, your milk production is FASTER.

Your body is constantly fine-tuning your milk supply to exactly meet your baby’s needs.Your body does not like to waste precious resources(West & Marasco 2009, p10). As your body becomes more efficient at supply and demand, your breasts will feel soft most of the time. This is normal. Milk production is designed to succeed (West & Marasco 2009, p13).


Mohrbacher, N et al (2003) The Breastfeeding Answer Book
Abbett, M (2008) A mother’s (and others) guide to BREASTFEEDING Issue 8
La Leche League of Great Britain (2009) Breastfeeding Peer Counsellor Programme
Van Veldhizen-Staas, C (2007) Overabundant milk supply: an alternative way to intervene by full drainage and block feeding in International Breastfeeding Journal 2007, 2:11 doi:10.1186/1746-4358-2-11
West, D & Marasco, L (2009) The Breastfeeding Mother’s Guide to Making More Milk


  1. Thank you for this wonderful article! My son is 8 months old and almost exclusively breastfed (we do baby-led feeding of solids but he rarely swallows anything). Although most women say that their breasts have become soft by this point, I still find myself becoming slightly engorged if he's gone for more than 2 or 3 hours without nursing (which happens at least once a day). His weight gain and output are fine. Could this mean my supply/demand system is not working correctly?

  2. Hi MonkeyMama!
    Welcome to the club! Everybody's milk supply is different, and it's not unusual to feel full periodically, especially during a bit of a lull after periods of increased breastfeeding. As I said in the article, your body is *constantly* fine-tuning your milk supply according to your baby's needs.
    If it helps, my youngest is the same age as yours, baby-led weaned (and probably eating about the same as yours too), and yes, I too know that slightly overfull feeling if my baby goes more than a couple of hours without feeding. Just like you, I'm not worried about my baby's weight gain or nappy output either. However, if you are concerned that this is a problem, it might help to talk it over with a breastfeeding counsellor.
    I hope you find that helpful!

  3. thank u for this article. i was having a melt-down this morning over my breasts not seeming not full enough, despite plenty of soiled nappies, and now i feel a lot more at ease and educatesd


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