One of the most common questions in any breastfeeding journey is how to know if you’re making enough milk. When it comes to pumping, there’s no universal guidance to ensure that you’re pumping the right amount of milk, because there are so many variables. These include how old your baby is, whether and how long you are away from your baby, and what your feeding goals are.

Whatever your situation, remember that feeding your baby is a marathon, not a sprint. Aim to find a feeding system that feels simple, sustainable, and adaptable. This will help increase the likelihood that your baby will get breast milk for a longer duration (which brings many health benefits¹) and minimize your own potential challenges and setbacks, both physical and emotional.

Once you understand your baby’s nutritional needs, including how to monitor feeding cues, you’ll be better equipped to maintain your supply while away from your baby. This will help you avoid producing too much—or too little—milk for your baby

Understanding your infant’s nutritional needs

In order to grow, all breastfed infants need between 24 and 30 ounces of milk a day between the ages of 1 and 6 months, according to pediatrician Dr. Laurie Jones, founder of Dr. MILK (Mothers Interested in Lactation Knowledge). That volume then shifts down gradually to 18 to 24 ounces a day between the ages of 6 to 12 months, in part because they’re adding solids to their diet. (Formula-fed infants need greater volumes because they metabolize formula differently.)

The number of pumping sessions you need to meet your infant’s nutritional requirements depends on two things: how much milk your breasts can physiologically store (which you cannot control), and how much milk you pump per session (which, to an extent, you can control).

Your breast storage capacity, for what it’s worth, has little to nothing to do with the size of your breasts. It simply means that the more milk your breasts can store, the fewer times you need to remove milk from them—by breastfeeding or pumping—to get the same volume. Conversely, the less milk they can store, the more frequently you’ll need to remove milk from them to keep up your supply. To get a sense of how many ounces of milk your baby is getting each day, you can multiply the amount of milk you’re able to pump each session by the number of pumping and direct-breastfeeding sessions you have in a 24-hour period. (You can learn more about this partnered dance of supply and demand in our article on understanding your supply.)

Monitoring your supply to match your baby’s needs

If you’re exclusively breastfeeding on demand, which Dr. Jones says is ideal for establishing your supply over the first four to six weeks of your baby’s life, the process should naturally match your supply with your baby’s needs. That’s because your baby’s suckling tells your breasts how much milk to produce.

When you pump, it’s helpful to bear in mind the above equation (pumped ounces per session times number of daily pumping or feeding sessions). You’ll want to continue to remove milk at a consistent frequency, being careful to pump anytime your baby feeds from a bottle, fully emptying your breasts each time. (Fascinating side note: this includes stimulating multiple letdowns, something you might not notice when breastfeeding, as your baby suckles through lulls to stimulate subsequent bursts of milk.)

Apart from keeping this equation in mind, the best way to match your supply with your baby’s needs is to closely watch for feeding cues—including responding to cluster-feeding demands to ramp up your supply. Look for hunger cues (fist to mouth, opening and closing mouth, alertness) alongside satiation cues (turning head away, closing mouth, drowsiness).

Remember, too, that it’s OK, if things change, or if you need to break your routine. Regularly doing so can negatively impact your supply, but occasionally spending an afternoon away from your baby without an extra pumping session should not. (And if a super strict routine stresses you out, try to ease into a more relaxed, cues-based routine.)

Tips to avoid undersupply

Undersupply is a top concern among breastfeeding parents. When you’re pumping, the basic rule of thumb is to pump every time your baby gets a bottle. And because your supply will start to drop, if you regularly go too long between breastfeeding or pumping sessions, this means you might need to re-strategize how you approach your evenings to maintain your supply, as your baby begins to sleep for longer stretches.

If your milk is delayed, your supply isn’t well established, or your baby is underweight or too weak to breastfeed, a provider may also recommend triple feeding. This intensive, temporary process involves breastfeeding, then pumping, then bottle-feeding every two hours throughout the daytime to increase your supply.

“You should have a lactation consultant and your baby's primary care doctor involved—and check your baby’s weight closely—to know how long to continue doing triple feeds,” Dr. Jones says. Because triple feeding is so demanding, she says, no one does it 24/7.

“We don’t want to dishearten people, but at a certain point, it’s best to help them accept where they are and move forward with that new reality,” Dr. Jones says. “It doesn’t mean you’re giving up breastfeeding. It means that your role might shift, and your baby might not get all their calories from breast milk. But if you combo feed with formula and breast milk, your baby still gets all the great benefits of breastfeeding.”

Tips to avoid oversupply

Because pumping stimulates production, pumping too often can lead to oversupply. And for all the concerns about producing enough milk to meet your baby’s nutritional and caloric needs, the issues associated with pumping more than you need to should not be overlooked.

Oversupply happens when your output is beyond what your baby needs (and drinks). This can put you at risk for engorgement, mastitis, and/or plugged ducts. You can feel a frequent uncomfortable fullness, which can cause you to continue pumping (to relieve pressure) more volume than your baby needs. The more often you do this, the more you’ll need to, because your supply corresponds with how often your breasts are stimulated and emptied.

This pumping-cycle trap is what Dr. Jones calls the “frozen-milk treadmill.” It involves more work for you and takes more time away from your baby. Worse, burnout resulting from too-frequent pumping sessions might make you less likely to reach your long-term feeding targets.

So what do you do if you find that you are experiencing frequent engorgement and stockpiling pumped milk in your freezer? “It’s time to work on gradually spacing out your pumping sessions,” Dr. Jones says. “Just remember: Feed the baby, not the freezer.” 

Maintaining your supply while being apart

There will be times when you’re away from your baby for a short period (for a hair appointment, for example) or for a full day (to attend a retreat) or even multiple days (to attend a work trip or wedding). So when should you pack your pump, and how frequently should you plan to use it?

Dr. Jones says a good rule of thumb is to pump if you’re going to be apart from your baby for longer than four hours. (If it’s less than or around that period, and your breasts feel full, you can always go to a bathroom stall and hand-express a little milk to relieve the pressure.)

“As long as you pump on a regular cadence when you’re away from your baby, you can keep your supply up,” Dr. Jones says. “If you’re planning to be away and want to build up a stash for your baby to use, you can pump off the end of each feed and after long stretches of infant sleep. Just don’t do this too often, or your body will think you have twins!”

Just as with pumping at home, you’ll want to continue to clean your parts, store your milk safely, and in certain situations, even pump and dump. You also may find it useful to think through how to pump in public, as well as familiarize yourself with your travel rights as a lactating parent.