Sudden Drop in Milk Supply? 15 Possible Culprits

Are you experiencing a sudden drop in milk supply? Here are 15+ possible reasons why you might be noticing a decreasing milk supply.

Decreasing Milk Supply

One day your child is nursing like a champ, and the next day, it’s like your milk completely disappeared.

A sudden drop in your milk can be startling and even depressing – especially when you aren’t sure why it’s happening!

I remember when this happened to me when Oliver was about 10 months old. He went from being able to nurse whenever he wanted to not being able to get a let down until he switched sides about 10 times.

I think both of us were in tears!

I think it’s important to know some of the “hidden” causes of a decrease in breast milk, which is what I’ll be talking about in this post today.

The good news is that when you’ve identified what the issue is, you can almost always recover – it might just take a little bit of time and patience.

Chances are, you’ve been breastfeeding for awhile. However, I strongly recommend signing up for our pumping and milk supply online class that is available 24/7. It has lots of tips for understanding milk supply and pumping a little bit more.

Originally published in February 2018. Updated November 2019.

Why is My Milk Supply Decreasing

Stress

This is seriously huge when it comes to milk supply. And unfortunately, the stress of having your breast milk supply drop can make stress levels even higher!

My lactation consultant said she always recommends moms go to get massages when they are dealing with a decrease in supply, simply because it helps them relax. If you are noticing a big drop in supply, try and eliminate any and all extra stress you might have. Your mental health will thank you, too!

Mint

Mint or peppermint is a known substance that can cause a decrease in supply…though there’s some debate on how much it actually takes.

Circumstantial evidence – one day when Oliver was about three months old, I noticed that my pump output was lower than usual. It seemed weird…and then I remembered I had eaten almost a whole bag of mint M&Ms. I don’t know if it was related… but who knows.

I have read it has to be actual mint or mint extract – not artificial.

Fenugreek

“What? I thought fenugreek was supposed to help your supply!”

Ah yes…Fenugreek. It’s often the first thing mothers turn to when they are struggling with their supply. I did, too!

And for some moms, it can help. However, it can have the opposite effect – especially with women who have a thyroid problem. Fenugreek can “influence the active thyroid hormone your body uses. This [can] make hypothyroidism worse and reduce milk production.” (source)

If Fenugreek is going to work, it will typically be seen in 24-72 hours…so if you aren’t feeling like it’s helping or hurting after that…I would probably just stop. It’s not worth smelling like maple syrup or causing you and/or baby gastric distress!

It has some other unsightly side effects, which I don’t love. According to Mosby’s Handbook of Herbs and Natural Supplements, by Linda Skidmore-Roth, it may also cause reduced absorption of medications.

While I’m not a huge fan of taking supplements for milk supply, there is a line of supplements from Legendairy Milk that is fenugreek free. I know a lot of people who rave about them.

Parsley

Parsley is another herb that is thought to decrease milk supply…so just be careful eating too much parsley in your meals!

Mirena IUD

I think most mothers know that certain forms of hormonal birth control can cause issues with supply.

This is why the mini pill is often prescribed to breastfeeding mothers because it doesn’t typically have an effect on breast milk supply.

A lot of moms are told to get an IUD, which can be a great form of birth control. However, there are many mothers who report having a drop in supply while using the Mirena IUD.

There was an article I read a while back that discussed this topic, though the website seems to be down. The author suggested that there are more moms who have their milk negatively impacted by it than we may realize, simply because they don’t realize the Mirena is the culprit.

There are plenty of mothers who can use the Mirena IUD with no effects whatsoever…but it’s impossible to know if it will affect your body or not until you try (and I’m not sure it’s worth the risk).

The copper IUD (Paragrad) is non-hormonal and should have no impact on your milk supply.

Sage

Sage is yet another herb to be careful with. A small amount shouldn’t do too much harm.

Decongestants

These are designed to dry up your sinuses….and unfortunately, they will dry your milk supply right up alongside them. Fortunately, you should be able to recover, but it’s best to avoid them as much as possible while breastfeeding. Mothers who are trying to dry up their milk supply are often told using a decongestant because it does a pretty darn good job.

Here is some good advice on cold and cough remedies compatible with breastfeeding.

Not Nursing on Demand

Timing schedules and not listening to your baby’s cues can make your supply suffer. It is SO important to feed on demand.

When you try and schedule feeds or limit when baby is eating – especially in the beginning – it goes against the natural process of milk production and your body may not make milk when it needs to.

The best advice I can give new moms is to stop watching the clock and just feed your baby when they want it (while, of course, knowing the signs that your baby isn’t getting enough).

Not Pumping When You Miss a Feed

Breast milk production is a supply and demand process – if you miss a feeding or a pump session, you are essentially telling your body you don’t need to make milk then.

Now, if you miss one pump session, it *probably* won’t affect things too much (though I do know some women where it has). However, it’s important to make sure you are regularly stimulating the breast to keep up your supply.

I recommend that you don’t go more than three hours during the day without nursing or pumping.

And if the baby gets a bottle instead of nursing, it’s important to pump around the same time. Even if your baby is eating from a bottle, your body doesn’t know that. You have to pump to tell your body, “Yes! Baby needs milk still!”

If you have trouble with pumping or aren’t sure how to use it, click here to check out our pumping and milk supply. class.

Wrong Size Flanges

So many mothers use the wrong sized flanges, and as a result, the pump isn’t able to remove milk as efficiently as it could be. As a result, if your body isn’t removing the milk as it should, it will start to think you don’t need as much milk.

I have heard good things about the Pumpin’ Pal Flange set, which makes it possible to get the perfect fit.

In our pumping and milk supply class, we discuss how to size your flanges.

Oregano

Yet another herb that’s associated with decreasing milk supply. Don’t go to crazy with your next Italian meal!

Low Milk Supply During Period

This is the one that I think is often the culprit for most mothers. I didn’t experience this with Jack, but I definitely did with Oliver, and it was horrible.

The first time it happened, I literally thought my milk supply had disappeared overnight. He would try and nurse and a let down would not happen…and it would take switching back and forth about five times for him to get one.

And after that, without fail, about two days before my period would start, the same thing would happen.

Unfortunately, there’s no way to know if you will be affected until it happens. On Kelly Mom, it suggests the following to help:

“For women who have this problem, calcium/magnesium supplements may be helpful. This practice has also been reported to eliminate most uterine cramping and some premenstrual discomfort such as water retention.

The recommended calcium supplement dosage is between 500 mg calcium/250 mg magnesium and 1500 mg calcium/750 mg magnesium (the higher dosage is generally more effective).

Calcium dosages this high should not be taken alone but as a calcium/magnesium (or calcium/magnesium/zinc) combination. Otherwise, the calcium will not be adequately absorbed into your body.”

It is recommended to start this regimen when you ovulate through the end of your cycle (source). Of course, please consult with your doctor before starting any new vitamins.

Drinking too Much Water

I know – this might sound shocking! But professionals agree – drinking too much water can actually hurt your supply, maybe even more so than not drinking enough.

So drink to thirst – and maybe a little more. But don’t overdo it!

Not Eating Enough Calories

It is suggested that breastfeeding mothers eat 300-500 extra calories a day. I recommend figuring out your BMR (basically, the number of calories you burn just being alive) and add extra calories to that amount.

With a lot of the lactation cookies and other lactation foods out there, I also think that the main benefit of these just come from them adding more calories.

I use my Apple Watch a lot, and it actually tells me how many calories I’ve burned throughout the day. I’ve found this to be helpful in making sure I eat enough.

I also recommend reading about Intuitive Eating – I think it can be helpful to learn to listen to your body to make sure it’s getting enough to make the milk for your baby!

Here are some great breastfeeding snacks to help keep you fueled. I am a BIG fan of these protein bars – they are the only ones I can stand eating (and you can get 10% off your order through this link).

Make sure you read this post if you want to lose weight while breastfeeding (without impacting your supply).

Too much exercise

This one kind of goes hand in hand with not drinking enough water or eating enough calories.

Often, when a new mother starts a new exercise regimen, it can be hard to know if you are eating and drinking enough. Moderate exercise shouldn’t affect your supply too much – just make sure you keep up those calories and drinking – and read these tips about exercise and breastfeeding.

The time I see exercise affecting a mother’s milk the most is when it’s a sudden change, and it’s a lot of intense exercises (such as Cross Fit).

Many breastfeeding mothers do these types of exercises and do just fine, but you have to make sure you are eating enough and not losing all your extra water through sweat!

Illness

When you are sick, it can be hard to eat and drink enough, and, quite frankly, even want to nurse. It can be common to see a drop in supply during this time. One thing to remember is that with most illnesses, you can still nurse your baby – in fact, it’s recommended so you can create the antibodies they need to fight it!

Solids

I’ve observed that many mothers see a drop in supply around the 8-9 month mark. As I’ve thought about it, I have a few suspicions as to why. The first one is that solids are becoming more a part of the baby’s diet.

I do believe it’s important to introduce solids and encourage them (and I don’t love the phrase “food before one is just for fun), however, it’s very important that breast milk remains the primary source of nutrition. If the baby starts to replace too much milk with solids, your supply will definitely take a hit.

If a mom has a drop around this time, I typically recommend cutting back on solids for a while until you can regain your supply. Always offer breast milk first and then solids shortly after.

We personally always do baby-led weaning with our children, which I feel always was a pretty natural transition to eating more solids without hurting my milk supply.

How do I Know if My Milk Supply is Low?

I think every mom worries about their milk supply at one time or another – it’s only natural to wonder if you are making enough (especially if you can’t know without looking

I’ve written about this topic in-depth in this post – The Ultimate Guide to Increasing Breast Milk Supply – but in general, here are a few basic tips for knowing if your milk supply has dropped:

• Baby is upset at the breast and can’t seem to get a letdown
• Lower weight gain (this does not always mean your supply is low – my boys had low weight gain because of reflux. But it’s certainly worth looking into)

Our course – Demystifying Pumping and Milk Supply – goes over milk supply in depth. Check it out here.

One thing I often see is when a mother’s supply starts to regulate, it seems like her supply has dropped. It Many mothers have a larger supply when their milk first comes in, and if they are pumping (which is generally not recommended until about 4-6 weeks), and suddenly go from making tons of milk to a lot less, they will think they are losing their milk.

This is not usually the case. The goal is to produce enough milk for your baby – and an oversupply is not as glamorous as you would think. In general, a mother who is pumping in addition to breastfeeding full time an expect to produce .25-2 ounces TOTAL from a pump session. In place of a nursing session, average is about an ounce or so an hour.

This is also why it’s important to practice paced feeding and keep bottles to 1-1.25 ounces per hour. I often see mothers who unknowingly “overfeed” their babies because they just give their baby all the milk they pump…and then when their supply regulates more, they worry because they can’t keep up.

When you keep to the 1-1.25 ounces per hour rule, it helps prevent this (and you can freeze that extra milk!)

I hope that this was helpful to anyone who is worried about a sudden drop in milk supply. Please feel free to leave a comment if you have any questions or concerns!

When Does Milk Supply Regulate?

Most women see that their milk regulates around 4-6 weeks.

OTHER BREASTFEEDING POSTS YOU MAY ENJOY:

• The Best Breastfeeding Tips for New Moms (Love, Moms Who’ve Been There)
• 13 Myths about Extended Breastfeeding
• The Ultimate Guide to Breastfeeding as a Working Mom