Too much breast milk? How to reduce oversupply

Sometimes you may feel like you’re producing too much breast milk, especially in the first few weeks of breastfeeding. Read on to find out if you really have an oversupply of milk, and what you can do about it

Breast milk is amazing, so having lots is a good thing, right? Well, not always... Some babies struggle with the fast flow that usually accompanies an overabundant milk supply. And mums with oversupply can often feel very uncomfortable, with frequently or constantly leaking breasts, and may be more likely to suffer from recurrent mastitis. 

Fortunately, there are a number of strategies that can help. But before you try any of these, ask yourself two key questions:

Do I really have too much breast milk?

Some symptoms of oversupply (outlined below) may have a number of other possible causes. It’s unwise to try to decrease your milk supply until you’re sure that oversupply is the underlying problem. Otherwise you could end up with less breast milk than your baby needs, particularly in the crucial first month when you’re trying to establish your supply.

Is oversupply a problem for me or my baby?

If you’re sure you have an oversupply of breast milk, but you and your baby are happy, there’s no need to do anything. Most cases settle down after the first few months. And as your baby grows, he’ll get better at dealing with a fast flow, and may come to enjoy it!

Leaking doesn’t always mean too much breast milk

During the first four to six weeks after your baby is born, your levels of the milk-making hormone prolactin will be increasing each time milk is removed from your breasts. In these early weeks, your breasts are learning how much breast milk your baby needs and how much to make every hour. As a result, excessive leaking and breasts that fill quickly – and even spray milk during let down – are common and normal.¹

At the same time, your newborn is also learning to coordinate the way he sucks and swallows, so some coughing and spluttering at the breast is also to be expected.

After around four to six weeks, surges in your prolactin will gradually decrease, and your milk production should start to follow a more straightforward ‘supply and demand’ process based on your baby’s needs.² But with so many hormonal changes happening in your body as a new mum, it’s not surprising that it can take time to adjust. Some mums find that their milk supply settles down quickly, while for others it may take a little longer.

Signs of breast milk oversupply in your baby

Overabundant milk supply seems to go hand-in-hand with a fast flow, especially during the first let down. Your baby may respond by coughing and spluttering near the start of a feed, clamping or biting down, or holding the breast very loosely in his mouth. He may come off the breast because the fast flow is a bit of a shock to him, and then cry because his feed has been interrupted. He’ll probably take in large volumes of milk, along with lots of air, and might spit up a lot and need frequent burping as a result. Be as gentle as possible if you’re burping him – jerky movements combined with a quickly filled belly can cause vomiting and upset some babies.

At the start of a breastfeed, the milk your baby is getting is relatively low in fat and consists mostly of lactose (sugar) and protein. As the feed progresses and your breast empties, the fat content of your milk steadily increases. In cases of oversupply, your baby may become full before he has completely drained your breast. This means that he is getting plenty of lactose-rich breast milk, but not as much of the high-fat milk that comes towards the end of a feed. Too much lactose, instead of a balanced meal, can be hard for babies to digest, resulting in explosive, frothy, green poos.

Paradoxically, in this situation your baby may want to feed constantly and be fussy in between feeds – although he’s taking in lots of calories, the low fat content of the milk means he never feels fully satisfied. This is because it’s the fat in food that makes us feel full. Think of the difference between eating dozens of rice crackers, and eating some cheese and biscuits – the cheese will make you feel more satisfied as it’s higher in fat.

However, all of the above symptoms can be caused by other things, such as reflux, allergies or even, conversely, a low milk supply. Only if they are combined with excessive weight gain is breast milk oversupply likely to be the cause. Babies are expected to gain around 900 g (2 lb) per month, but in cases of oversupply, they will put on much more – often around double that.¹ If your baby appears to have symptoms of oversupply but is gaining an average amount of weight, see a lactation consultant or breastfeeding specialist for advice.

Oversupply symptoms you may experience

Mums with too much breast milk often experience uncomfortable feelings of engorgement and tension and constantly feel overfull.³ As we have seen, leaking breast milk is normal in the first six weeks or so, and not usually a sign of oversupply. But if you’re still getting soaked every time your baby feeds after this period, it may be an issue.

Because a baby can’t always drain a very full breast, it’s also common to experience blocked ducts or repeated bouts of mastitis as a result of oversupply. However, these problems may also have other causes.

How to decrease milk supply

If you’ve established that you have too much breast milk and it’s a problem, here are a few simple measures that may help. For some mums these are sufficient:

• Try laid-back breastfeeding. Feeding in a reclined position, or lying down, can be helpful because it gives your baby more control. He can set the pace and lift his head for a break if your flow is too fast for him. Remember to place a towel underneath you to catch any excess milk!
• Relieve pressure. If your breasts are very uncomfortable you can hand express or pump a little milk to relieve them – but try to express the smallest amount possible. Each time you remove milk, you’re sending your breasts a message to produce more. So, while expressing can bring temporary relief, in the long run it could make the problem worse. If you need to express and store milk for times when you’re apart from your baby, it’s best to wait until you’ve addressed your oversupply.
• Try nursing pads. If you're leaking milk, popping disposable nursing pads or milk collection shells inside your bra could help you stay dry.

Avoid lactation teas and supplements. If you’ve been drinking mother’s milk teas, eating lactation cookies or taking herbal supplements to encourage breast milk production in the early days, make sure you stop – these could now be part of the problem.

Block feeding to reduce milk supply

If you’ve tried the above and you or your baby are still having problems, a technique called block feeding could get your supply to a more manageable level. But get advice from a lactation consultant or breastfeeding specialist before trying this method.

With block feeding, you breastfeed your baby whenever he wants for a period of four hours, but from one breast only. Your other breast will become very full of milk. As your breast milk contains something called ‘feedback inhibitor of lactation’ (FIL), the excessive fullness signals that breast to slow down milk production. It’s your body’s way of ensuring that your breasts don’t fill up endlessly.

Try this technique for 24 hours, alternating breasts every four hours. If there’s no improvement, you can increase the length of the blocks to six hours.

Full drainage and block feeding technique

If there’s still no improvement after another 24 hours, there’s another version of this technique that can be suitable for mums with more extreme oversupply, called ‘full drainage and block feeding’.³

With this method, you use an electric breast pump to fully drain your breasts at the start of the day, then feed your baby immediately afterwards. The flow will be slower, which means your baby should be able to cope better. He’ll also get more of the higher-fat milk that comes at the end of a feed, so will feel more satisfied.

You can then begin block feeding for four hours at a time, as above. If this isn’t effective, switch to blocks of six, eight or 12 hours the next day, depending on how severe the oversupply problem is. Talk to a healthcare professional before attempting this technique.

You may not need to fully drain your breasts again after the first instance, but some mums need to do it once or twice more. Some mums notice an improvement within one or two days, or a little longer, but block feeding should not be continued for more than five days.