Combination Feeding: Supplementing Breast Milk With Formula

One of the first big decisions you’ll make for your baby is choosing how they’ll receive their nutrition: through breastfeeding, expressed breast milk, or formula. Although this decision may seem simple, there are many layers to this choice and several factors at play. In some situations, breast milk and formula together may be the best option for your baby. This is combination feeding, also known as combo feeding or mixed feeding, and is a common method of feeding when supplementation is necessary for your baby.¹

Although this article discusses combination feeding, it’s important to note that the American Academy of  Pediatrics (AAP) recommends exclusively breastfeeding your baby for the first six months of life. Exclusively breastfeeding is always encouraged if feasible for the mother and baby.² The introduction of formula can put a mother’s milk supply at risk. It’s also been associated with early cessation of breastfeeding.^3,5,7 If your healthcare team advises formula for supplementation, please work closely with a lactation consultant to protect your breast milk supply.³

Some may wonder, can you breastfeed and formula-feed a baby? The answer is yes; giving your baby the health benefits of breast milk is always a good thing!¹ Giving both formula and breast milk to meet a baby’s nutritional needs is called combination (combo) feeding.¹ This combo feeding method may be by choice or necessity. Some may decide that combination feeding will work best for their baby and family, while others move to combo feeding to meet their baby’s health needs. Some mother-baby duos experience challenges in their breastfeeding journey that require supplementation with formula, such as low breast milk supply or separation of the mother and baby.^3,4

You can practice combination feeding in different ways. Most commonly, you’ll see parents combine breastfeeding and formula feeding or expressed breast milk feeding and formula feeding from bottles.

Remember, the AAP recommends exclusive breastfeeding for the first six months of a baby’s life.² Unfortunately, even with the will and want to breastfeed exclusively, sometimes, situations arise that call for combination feeding and supplementing with formula. Breastfeeding and formula may be necessary due to health concerns for the baby or different maternal circumstances.³

The situations below may indicate that combination feeding could be helpful for your baby. It’s always good practice to reach out to your healthcare team to discuss how to supplement with formula before giving it to your baby.¹ Here are some possible combination feeding indications:

It’s normal for newborns to lose weight after birth, but you should monitor how much weight they’re losing. For exclusively breastfed babies, a loss of greater than 8-10% of the weight may indicate a concern with breastfeeding.³ Before initiating supplementation with formula, it’s best practice to have a lactation consultant evaluate you to discuss baby’s latch and breast milk supply.^3,4,7 There may be a problem that can be corrected.^3,4

In some instances, though, that isn’t the case. Your doctor may recommend supplementing with formula alongside breast milk to help your baby gain weight appropriately. Formula supplementation can be temporary as the mother works to increase her milk supply.³

If a mother and baby are separated and a limited amount of expressed breast milk is available, combination feeding with formula would be necessary to meet the baby’s needs.⁴

Note: If you decide that combination feeding is what will work best for your baby and family, you should establish your breast milk supply first.¹ This may take a few weeks but is important to help maintain the mother’s breast milk supply.

Combination feeding will most commonly involve introducing a bottle. If possible, the most important thing to do before introducing a bottle is to establish a breastfeeding relationship between you and your baby.¹ This is when baby comfortably breastfeeds, successfully sucking and removing breast milk. It’s best to delay bottle introduction until about four weeks of life.⁶

If you want to continue breastfeeding and give a bottle, the technique of paced bottle feeding is recommended.^3,4,7 Bottles offer a quicker flow of milk to the baby versus breastfeeding, where the baby has to work harder to pull milk from the breast. Babies can recognize the ease of bottle feeding and be more resistant to returning to the breast. Paced bottle feeding is a method where the parent will hold the bottle level, encouraging baby to pull the milk from the bottle by sucking, mimicking the needs of breastfeeding. This can help make the transition back and forth from bottle to breast easier.⁶

It’s very possible to be successful with breastfeeding and bottle feeding when introduced correctly. If introducing your breastfed baby to a bottle causes concern, contact your lactation consultant to discuss alternative feeding methods.

When you’re breastfeeding, expressing breast milk, and giving bottles (formula or breast milk), life may feel a bit chaotic. It may even feel confusing as you figure out how to combine breastfeeding and pumping or whether you can even mix breastfeeding and formula. So, what’s the best way to help the chaos? Create a breastfeeding and formula feeding schedule that works for you and baby and protects your breast milk supply!

When combination feeding, a good rule of thumb is to always give breast milk first. This could be through breastfeeding or bottle feeding expressed milk. As we know, breast milk is full of amazing nutrients and health benefits. As a result, you should give it first.⁴ This may mean breastfeeding before formula or giving a bottle of expressed milk followed by formula. Doing this ensures the baby is removing milk from the mother’s breast to help with her supply. It will also lower the risk of wasting breast milk when bottle feeding.⁴

See below for two sample breastfeeding and formula feeding schedules:

1. Breastfeed: Always breastfeed first when combination feeding. Your baby will not only receive the benefits of breast milk, but this will also help with your milk supply. If baby only takes one breast during the feed, it will be important to pump the unfed breast. This protects your milk supply.¹
2. Formula feed: Using the paced bottle feeding technique, you give your baby formula as directed by your healthcare team.^3,4,7 When giving them formula, it’s very important to learn how to correctly mix and safely prepare powdered formula. Follow the CDC’s recommendations for preparing powdered infant formula.

For the Mom Who’s Pumping and Giving Formula

1. Express milk and prepare the breast milk bottle: Pump and pour milk into a bottle. Or, you can prepare some previously pumped expressed milk in a bottle.
2. Feed expressed milk: Using the paced bottle technique, feed your baby expressed milk.^3,4,7
3. Prepare and feed formula: Based on how much expressed milk baby took and their hunger cues, prepare a formula bottle. Using the paced bottle technique, feed your baby formula. Watch for baby’s cues to identify when they’re full.
4. Pump, if not completed before feeding: If you didn’t pump at the start of the feed, you should pump both breasts after baby stops feeding to maintain your milk supply.

It’s important to note that if full feeds are being rotated between breast milk and formula after every formula feed, the mother should be pumping to maintain her breast milk supply.

How To Maintain Your Milk Supply While Combo Feeding

Breastfeeding is a supply-and-demand process that puts combination-feeding mothers at risk for a drop in milk supply. It’s always helpful to breastfeed when possible, even in combination feeding.⁷ A baby can stimulate the breast and remove milk best. This signals to the mother’s body that breast milk production is still needed.⁷ It’s crucial for mothers to express milk as frequently as they would bring their baby to the breast to feed in order to maintain a supply to meet the baby’s needs. This will average around eight to 12 breastfeeding sessions and/or pumping sessions. If possible, wait to start combination feeding until your milk supply is established in the first few weeks.¹

A good rule of thumb is to express milk every time your baby is feeding with a bottle.^1,7 If you’re unable to bring your baby to the breast to feed, regular pumping will be necessary. The same goes for if your baby feeds on only one breast; make sure to pump the unfed breast once the baby is finished.¹ Working with a lactation consultant while combination feeding can be very helpful. They can provide recommendations to maintain your milk supply. They can also help you work on returning to exclusive breastfeeding (if that’s the end goal).

Whether combination feeding started by choice or out of necessity for you, it’s wonderful that your baby is receiving breast milk! Please make sure to consult your healthcare team before introducing formula to your baby. Also, work closely with your lactation consultant to maintain your breast milk supply when combining breastfeeding with formula. You got this, mama!