10 Reasons For A Sudden Drop in Milk Supply & How to Fix It!

There are a few things more stressful for a breastfeeding mother than a sudden drop in milk supply.  This is especially true for working moms who are trying to pump enough milk for baby’s daycare bottles or moms who exclusively pump.  There can be many causes to a sudden drop in milk supply. Some are completely normal and part of your breastfeeding journey, while others require some action in order to hopefully get your supply back up to a normal level.  And while there are many ways to increase breast milk supply fast, it is important to pinpoint why exactly you are experiencing a dip in milk supply so you can remedy it.

Related article: How to Increase Breast Milk Supply Fast

We polled hundreds of working moms who have experienced a sudden drop in milk supply to ask them what caused it.  We received loads of answers and have gathered the most frequent causes here. Read through them with your specific situation in mind to help you figure out why you are experiencing a dip in milk supply.

Related article: Supplementing with Formula: Advice from Experienced Moms

1. Your milk supply may be regulating.

Many moms experience an oversupply of breast milk in the weeks following their baby’s birth.  At around 6 weeks (give or take one week or two), your milk supply will begin regulating to your baby’s needs.  Your breasts may feel less full and your baby may even be a little fussy at the breast. Do not be concerned! This is your body adjusting to the amount of milk your baby is taking at each feed.  Your body will regulate more as your baby gets older. This is a good thing as an oversupply of breast milk can present many painful challenges.

Related article: 12 Ways to Treat a Clogged Milk Duct Fast

2. Get a new breast pump or check the suction on your current pump.

If you are using a breast pump from a previous pregnancy or are using one a friend gave you, it’s time to get a new one.  Just like all motors, your breast pump motor can wear out over time thereby losing suction. This loss in suction can cause your breast pump to become less efficient at emptying your breasts of milk.

By law, your insurance company must provide a new breast pump for every pregnancy (no matter how close or far apart your pregnancies are).  Check out our article on How to Get a Free Breast Pump for more info on how to get a new one for free.  A new breast pump with stronger suction may be what you need to increase your breast milk supply.

Related article: Pumping Laws at Work Explained

Alternatively, if you did purchase a new breast pump, try to determine if the suction is still as strong as it was when you started using it.  If you are an exclusive pumper or pump more than you nurse due to your work schedule, your breast pump may be wearing out. Adjust the suction levels on your pump to see if they change as drastically as they did when you first got your pump.  If you don’t feel they are or you notice strange sounds coming from the motor when you adjust the settings, reach out to your breast pump manufacturer. Most breast pumps have a one-year warranty. Many of the moms we polled said they were overnighted a new pump when they contacted the manufacturer about issues with their pump motors.

Related article: Strawberry Breast Milk: 6 Causes of Blood In Your Breast Milk

3. Replace pump parts.

No matter what brand of pump you own, there are parts that need to be replaced every few months in order to keep your pump working at max efficiency.  This is due to residue build up that can occur in small crevices that are hard to clean and the gradual stretching out of or micro-tears in parts after repetitive use.  If you haven’t replaced your parts recently (or ever), consider purchasing replacement parts:

  • Membranes + Valves for Medela pump users need to be replaced once every 2-3 months for working moms who are pumping 2-3 times a day at work.  Consider replacing them once a month if you exclusively pump.
  • Duck valves for Spectra pump users need to be replaced once every 2-3 months for working moms who are pumping 2-3 times a day at work.  Consider replacing them once a month if you exclusively pump.

Breastfeeding replacement parts may be covered by your insurance plan.  In order to check and see if you can get replacement parts (and other accessories) for free, check with your insurance provider or allow Aeroflow Breast Pumps to do it for you at no cost.  Aeroflow is a breast pump supplier that works directly with insurance companies all day long to obtain breast pumps and pumping supplies for moms. Accordingly, they know the ins and outs of what’s covered and what isn’t for most insurance plans. Keep in mind, too, that breastfeeding supplies are covered under Flexible Spending Accounts (FSA) and Healthcare Savings Accounts (HSA).

Related article: Pumping Supplies: All the Essentials You Need

4. You may be about to start your period.

We know.  Talk about adding insult to injury, but your period can affect your breast milk supply.  Ovulation can cause blood calcium levels to dip in some women.  This dip in calcium translates into a drop in milk supply. Calcium levels tend to return to normal levels around the second or third day of a woman’s menstrual cycle.  In order to prevent a sudden drop in milk supply from your impending period, you can take a calcium/magnesium supplement about a week before you expect to start your period and stop on the second or third day after aunt flow returns. 

Related article: How to Thicken Breast Milk Naturally – 4 Effective Methods!

Calcium on its own cannot be absorbed by the body which is why you need the calcium/magnesium combo.  The recommended dosage for breastfeeding moms is between 500mg calcium/250mg magnesium (1 tablet) and 1500mg calcium/750mg magnesium (3 tablets).  Where you fall in that range depends on your diet. If your diet is high in calcium rich foods, you can start with the lower dosage. If you don’t eat lots of dairy, beans, or green leafy vegetables, try the higher dosage.  The higher dosage will likely yield quicker results.

Also, remember to continue taking a prenatal vitamin as long as you breastfeed and/or pump. To see more information about breastfeeding during your period check out our article Breastfeeding While On Your Period? 7 Helpful Tips for Your Milk Supply.

Related article: Breasts Not Responding to Pump Anymore? Try This.

5. Use the correct flange size.

If pumping is uncomfortable or even painful for you, chances are you aren’t pumping correctly.  By not pumping correctly, you may not be expressing enough milk which can cause your body to slow its milk production.  If you think this may be the case, check to see if you are using the correct flange size for your pump. Check out our article on How to Determine Your Correct Flange Size for more guidance on identifying your best breast pump flange fit.

Related article: The Complete Guide on How to Pump Breast Milk

Another thing to keep in mind is that your nipple may change size as you breastfeed and/or pump.  If you have been pumping for months and had no problem until now, try changing your flange size. Maymom offers a variety of Medela and Spectra compatible flanges at a lower price than purchasing directly from the big brands (and they work great, too).

6. Make sure you are keeping your water and calorie intake up.

It’s easy to get preoccupied with your new baby or work or life in general when you have an infant.  If you notice a sudden dip in milk supply, evaluate whether you are drinking enough water and eating enough calories.  Your body needs both in order to make breast milk. Breastfeeding a baby can burn between 200-500 calories a day. And that’s beyond the normal amount of calories your body burns to perform its basic metabolic functions.

If you don’t think you are drinking enough water, try keeping a tumbler full of water with you at all times.  If you struggle with the taste, try sweetening it with something like True Lemon. If you are staying hydrated but are struggling to get in calories, add in a few healthy snacks each day.  Check out our recipe for Lactation Fudge for a high calorie and healthy breastfeeding snack. Or you can try eating Oreos to get your calories up. Some moms claim they help with milk supply. We advocate for healthy options to get calories up, but do whatever you can in this season of life! You can also check out our lactation oatmeal recipes. Oatmeal is known to increase breast milk supply and it’s tasty, too:

7. Stop using supplements.

If you are taking fenugreek or any other supplement because you were told it helps increase breast milk supply, try stopping it and see if your supply goes back to normal.  While there are many breastfeeding supplements that can boost milk supply, some women notice the opposite effect. There isn’t any clinical evidence as to why this occurs, but about a third of the breastfeeding moms we polled said fenugreek and other similar supplements had an adverse effect on them and caused a sudden drop in milk supply. Try stopping the supplement for 24-48 hours to see if your milk supply returns to normal.

Related article: 10 Most Common Reasons (& Remedies) for Breastfeeding Pain

8. Are you pregnant?

Do not believe anyone that tells you you can’t get pregnant while breastfeeding.  While the chance is slim if your period hasn’t returned, your baby is fed on demand (not always possible for working moms), and your baby is less than 6 months old, there still is a small chance that you could get pregnant during this window.  And as soon as any of those three things is no longer true, all bets are off. If you are experiencing a sudden drop in milk supply, sensitive nipples, and have had sex recently, you may want to take a pregnancy test to rule this out as a possible cause.

Related article: Accidentally Went 6 Hours Without Breastfeeding? Don’t Panic.

9. Your baby’s age may be causing a sudden drop in milk supply.

As your baby gets older and begins to start eating solid foods, your baby will naturally start taking less milk from you.  While it is recommended by the American Academy of Pediatrics to continue to offer your baby the same amount of breast milk or formula until he/she is twelve months old, you may notice a dip in supply around 9-10 months.  This is the age where babies finally understand what food is and begin to eat more.

You may introduce solid foods to your baby at 6 months, but more than likely he/she will simply play with the food or ignore it all together at first.  This is all totally normal. It’s not until they are a little older that they understand the whole food concept and begin digesting more. Make sure you continue to offer your breast or a sippy cup of breast milk before and after each meal.

Related article: How to Transition Your Baby to Milk: Everything You Need to Know

10. Eliminate stress.

We realize how difficult this is for everyone–and especially working breastfeeding mothers–but try your best to eliminate stress in your life.  Stress can impact your body negatively in many ways, and for lactating mothers it can manifest by causing a sudden drop in milk supply. Do you have something stressful going on at work?  Is a family member sick or have you had a sudden death of a loved one? Is your daily schedule too demanding?

Related article: Working Mom Guilt & Encouragement

Try your best–for you and for your baby–to eliminate or lessen stressors if possible.  If it’s not possible or is beyond your control, then make pump sessions as peaceful as possible.  Play music, look at pictures of your baby, or just close your eyes and relax for the 15-20 minutes you are connected to your pump.  Another suggestion would be to find support either through a breastfeeding group in your area (check with local hospitals or through your local La Leche League group) or on an online group (search ‘working moms’ on Facebook).

If you have ruled out all of the above as the reason you are experiencing a sudden drop in milk supply, reach out to a lactation consultant or your OBGYN.  They can provide you with advice and solutions based on your past medical history and current situation.  

And finally, take a look at our article on How to Increase Breast Milk Supply Fast if you have identified what the problem is and are now looking for ways to get your breast milk supply back.  Just like we polled our working moms on the causes of dips in supply for this article, we also asked what helped their milk supply return to normal. All of that information is available here.

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Shannon founded Work Breastfeed Mom in 2019 during her second round of pumping at work. She was tired of googling the same pumping questions over and over again, and discouraged at the lack of websites aimed at working breastfeeding moms. So, she created one herself. Shannon lives, works, and doles out Puffs to her little people in sunny Florida. She has her MBA and works as a strategic planner for a large healthcare system. She is passionate about coffee, memoirs, paddle boarding, and skincare routines. Shannon is mom to Scarlett and Ivy, and hopes to have more babies if her career allows.