Breastfeeding can feel overwhelming and confusing, especially if you’re new to it. Whether you’re nursing, pumping, or doing a bit of both, it’s easy to feel unsure about making enough milk, how often to pump, or if you can use formula without losing your supply.
As an International Board Certified Lactation Consultant (IBCLC), I’ve helped thousands of parents navigate these questions. The truth is, breastfeeding is natural, but it’s not as natural as breathing its more like learning to walk. With the right information and support, it becomes much easier.
Let’s explore what affects milk supply, how to increase it, how often to pump, and how to protect your milk production if you’re also using formula.
Factors Affecting Milk Supply
The foundation of milk supply lies in a simple concept: the more milk you remove, the more your body makes.
Imagine your breasts as an ice maker. If you don’t remove ice from the bin regularly, the sensor eventually signals that the ice maker is full and stops producing. However, when you keep scooping ice out consistently, the machine continues to produce.
Your breasts work similarly. When milk is removed, either by your baby or a pump, your body receives the signal to produce more. The less frequently milk is removed, the slower production becomes.
Several other factors can influence how effectively your milk-making “ice maker” functions:
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Frequency of milk removal: Long gaps between nursing or pumping sessions signal to your body to produce less milk.
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Latch or pump fit: A shallow latch or an ill-fitting pump flange can prevent milk from being removed efficiently. If pumping or breastfeeding causes discomfort, don’t hesitate to seek help.
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Hydration, nutrition, and rest: Your body requires consistent calories, fluids, and rest to produce milk.
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Hormonal or medical conditions, such as thyroid imbalance, PCOS, or retained placenta tissue, can affect milk supply. Stress and fatigue can also interfere with the letdown reflex, making it harder for milk to flow. Additionally, certain medications, especially those with estrogen, can decrease supply.
What Is Normal Milk Output?
Many new parents worry they’re “not making enough” when, in reality, they’re producing exactly what their baby needs.
In the First Few Days, your breasts produce colostrum, a thick, nutrient-rich milk that’s made in small but mighty amounts, usually 1 teaspoon to 1 tablespoon per feeding. This is exactly what a newborn needs.
A baby’s stomach size grows rapidly in the first week:
-Day 1: Size of a cherry (5–7 mL per feeding)
- Day 3: Size of a walnut (22–27 mL)
- Day 7: Size of an apricot (45–60 mL)
- By 1 Month: Size of an egg (80–150 mL)
Knowing this can be reassuring because newborns don’t need large amounts of milk at first; they just need frequent feeds to keep their milk supply up.
Usually, by 2–4 weeks postpartum, most exclusively breastfeeding parents pump about 2–4 ounces (60–120 mL) combined per session. Pumping output varies widely depending on the time of day, the number of sessions you’ve had, and whether you’re exclusively pumping or nursing too.
How to Increase Milk Supply
If you’re trying to increase supply, the goal is to help your body remove milk more frequently and more completely. Here are some helpful tips:
1. Pump or Nurse Frequently:
- If you’re exclusively pumping, aim for 8-12 pump sessions in 24 hours during the early months. That’s about every 2–3 hours, just like a newborn would feed.
- If your baby is exclusively breastfeeding, remember that they can’t overfeed from the breast. Think of it like an all-you-can-eat breastaurant for your baby.
- Remember, the more you empty your milk supply, the more your body knows to refill it.
Even short, consistent pumping sessions signal your body to continue producing milk. Missing sessions, especially early on, indicate to your body that demand has decreased, and supply can follow suit.
2. Try Hands-On Pumping
Before and during each pumping session, gently massage your breasts. This can help you remove more milk and increase output. Studies have shown that “hands-on pumping” can boost milk volume and fat content.
3. Check Your Flange Fit
Ensure that your nipple moves freely in the tunnel without rubbing or pulling too much areola. Pain, friction, or poor suction are all signs that you may need a different size flange.
4. Add a Power Pump Session
Power pumping mimics a baby’s “cluster feeding” pattern, which signals your body to increase milk production.
Try this routine once a day for a few days:
- Pump for 10 minutes
- Rest for 10 minutes
- Pump for 10 minutes
- Rest for 10 minutes
- Pump for 10 minutes
You’ll often notice results within a week. It doesn’t have to be every pump session. I usually advise my clients to add one power pump session first thing in the morning and the last pump session before bed.
5. Spend Time Skin-to-Skin
Even if your baby bottle-feeds, daily skin-to-skin time helps release prolactin and oxytocin, the hormones responsible for milk production and letdown.
6. Take Care of Yourself
Hydration, nutrition, and rest are more important than perfection. You don’t need to drink gallons of water or eat lactation cookies all day. Just stay hydrated, eat a balanced diet, and rest when you can.
Your pumping schedule depends on your goals and baby’s feeding routine:
- Exclusively pumping: 8–12 times per day, including once overnight.
- Pumping at work: Pump every 2-3 hours or as often as your baby eats.
- Occasional pumping: Add one session a day, usually in the morning when supply is higher.
How to Maintain Milk Supply While Combo Feeding/Using Formula
Many families choose to use both breast milk and formula. Whether it’s for flexibility or supplementation, combo feeding can absolutely work.
However, it’s crucial to understand how formula affects milk production so you can protect your supply while still meeting your baby’s needs.
Key difference - Formula Digests More Slowly
Breast milk digests quickly, usually within 1.5 to 2 hours, while formula takes longer for a baby’s body to break down (often 3–4 hours). Consequently, your baby may go longer between feedings after a formula bottle, which can unintentionally reduce the number of times your breasts are emptied in a day.
Less milk removal signals to your body to produce less milk.
Solution - Add in Extra Pump Sessions
If you’re giving your baby formula, try to pump anytime your baby receives a formula feeding. This maintains your milk-making rhythm even when your baby isn’t nursing. While you don’t have to match it perfectly, aim to keep it as close as possible.
If you can’t pump for every bottle, aim to make up for it later in the day with a “catch-up” pump or a power pump session.
Avoid the “Top-Up Trap”
Here’s how the top-up trap typically occurs:
Baby seems fussy or hungry after breastfeeding.
Parent offers a small bottle of formula “just to top off.”
Baby drinks the bottle.
Baby stays full longer and nurses less often.
Parent pumps less or skips a session.
Milk supply slowly decreases, leading to more bottles.
It’s a cycle that can unintentionally replace nursing sessions with formula, gradually lowering supply.
If your baby still seems hungry after breastfeeding, try offering both breasts again, switching sides a few times, or adding a short pumping session to stimulate extra milk production. If you’re genuinely concerned about baby’s intake, an IBCLC can perform a weighted feeding to determine how much milk baby transfers during a session.
How to Protect Your Supply While Using Formula
Pump anytime your baby skips a feed or takes a full bottle.
Use a high-quality, efficient breast pump to ensure full milk removal.
Incorporate skin-to-skin contact to boost hormones.
Maintain a consistent pumping routine. Your body doesn’t differentiate between baby and pump; it only recognizes that milk is being removed.
Combo feeding doesn’t necessarily mean depleting your supply. It simply involves finding the optimal rhythm between your baby, your body, and your goals.
Q&A/Common Milk Supply Questions
How can I determine if my baby is receiving sufficient milk?
After the first week, you should observe at least six wet diapers daily, steady weight gain, and a generally content baby after feeding. Additionally, listen for sucking and swallowing sounds during breastfeeding. An IBCLC can confirm this by conducting a weighted feed (weighing your baby before and after nursing to measure milk transfer).
Is it normal to only pump a few ounces?
Yes! Most individuals pump between 1 and 3 ounces from both breasts combined during each session. The amount produced varies depending on the time of day, frequency, and individual storage capacity.
Can I mix milk from different sessions?
Yes! Simply cool freshly pumped milk before adding it to already chilled milk. Keep the mixture dated by the oldest milk.
How long can breast milk be left out?
At room temperature (up to 77°F), milk can last up to 4 hours. In the refrigerator, it can last for 4 days. In the freezer, it can last up to 6 months.
Should pumping cause pain?
No. Pumping should feel like gentle tugging, not pain. If you experience pain, check your flange fit or suction settings.
Why Working With a Lactation Consultant Matters
One of the most significant differences I observe between families who feel confident about breastfeeding and those who feel frustrated is the importance of early lactation support.
You don’t need to wait until something is amiss to seek assistance from an IBCLC. In fact, scheduling a consultation early, even within the first week, can prevent most issues before they escalate.
A lactation consultant can:
- Evaluate your latch or flange fit
- Assess milk transfer and weight gain
- Develop a personalized feeding or pumping plan
- Assist you in combining formula and breast milk without compromising your supply
- Troubleshoot pain, clogs, or dips in production
- Provide reassurance and realistic next steps
- If you’re experiencing nipple soreness, clogged ducts, or low milk output, or if you simply want peace of mind, don’t hesitate to reach out. The sooner you seek help, the easier it is to adjust your plan and safeguard your milk supply.
Conclusion
Whether you’re exclusively breastfeeding, exclusively pumping, or combining both methods, just know that every ounce of milk you produce is precious.
Your body is remarkable in its ability to adapt to your baby’s needs, your schedule, and even your emotions.
Remember: the more milk you remove, the more your body will produce.
If you’re supplementing with formula, pumping consistently and maintaining a connection with an IBCLC can help you maintain a strong milk supply and ensure your baby receives proper nutrition without any guilt or pressure. Finding the right breast pump that fits your needs is also crucial.
You are doing an incredible, loving job of nourishing your baby in the way that best suits your family’s unique needs. Trust the process and walk forward with confidence. You are stronger and more capable than you know.
