The Ultimate Guide to Combi Feeding - Mixing Breastfeeding and Formula

Can you mix breast milk and formula? Yep, you can, it’s called combi feeding. Breastfeeding mums can embrace the benefits of combi feeding from birth to suit their family’s lifestyle. Learn when to introduce a bottle to a breastfed baby and more, with combination feeding routines, safety tips, and mum-hacks you wish you’d read sooner!

What is Combination Feeding? 

Combination feeding, also known as combi feeding or combo feeding, is when a baby follows a breastfeeding and formula schedule. Breastfeeding mums can breastfeed at the breast or express breast milk whilst also feeding their baby formula milk at other times.

More families are leaning towards the flexibility of combi feeding because you can share feeding responsibilities more evenly. It also allows parents to fit their work, lifestyle, and other commitments around a breastfeeding and formula schedule.  

Learn more: Breastfeeding or Baby Formula: Which Feeding Method is Better? 

Benefits of Combination Feeding 

The convenience of combination feeding is sometimes overlooked and deemed as “too much work” but it can be quite the opposite, and you can reap the benefits of both. 

Flexibility for the Family 

Dads, partners, and caregivers can share that special bonding moment with a baby when they can be included in feeds. It also means that feeding times aren’t just for a breastfeeding mum to give, as it gives the whole family versatility on the where, who, when, and how. Whether it’s breast and formula milk in one bottle or one or the other, your baby’s nutritional needs are being met.  

When you breastfeed and bottle feed, it can eliminate the pressures on nursing mums to deliver every day. That’s why for some families, combination feeding works best for their baby but also for a mother’s well-being.

Benefits of Combination Feeding for Mums 

Not all newborns take to breastfeeding quickly, so combi feeding offers mums peace of mind that they are getting the best of a mother’s breast milk and a full feed with formula milk too. A combination feeding schedule not only takes the pressure off of mum to breastfeed each time but also gives her the head space to think about non-baby-related things. 

Mum, Akshara, said that combi feeding “gave us the best of both worlds”. She went on to say, “Both of us were able to experience the intimacy and emotional bonding of feeding in the early days and weeks,” and “more equitable division of labour between parents that set the tone and balance for our future parenting roles”.  

Breastfeeding mums returning to work can confidently embrace a combi feeding routine with the right breast pump, designed for mobility and convenience, as it supports their milk supply while adapting to being away from their baby for longer periods. Also, mothers with a low milk supply can mix breast milk with formula milk to top up their baby’s feeds without worrying about expressing enough milk for the day.  

Although it’s something you don’t often consider before giving birth, there’s a chance that you will need longer to recover in hospital after your baby is born. For medical reasons, it may not be safe to breastfeed straight away, so combi feeding can be a good compromise if you find yourself in this situation. 

Combination Feeding Newborns 

There are many reasons why your baby may struggle initially with breastfeeding.  

• Poor latch due to tongue tie 
• Born prematurely 
• Traumatic delivery 
• Strong letdown of breast milk 
• Medications at birth or during delivery 

Learning how to combine breast and formula milk will keep your baby well-nourished while you establish your breast milk supply and combi feeding routine. If you’re wondering how to get your baby to take a bottle, try using a baby bottle with a teat that mimics the shape of the breast, such as the Lola&Lykke NaturalFlow Baby Bottle. 

When to Start Combination Feeding 

Even if you haven’t established a feeding routine yet, or you are well underway with formula or breastfeeding, you can start combi feeding any time.  

Advice from healthcare professionals is to wait until you have established breastfeeding before introducing a bottle. Every mother and baby are different, your breast milk supply is usually fully established and settled down around 4-6 weeks after birth. 

Can I Combi Feed from Birth? 

Yes, and it is perfectly safe to do so. 

Some parents choose to combi feed from birth because there are other factors at play. For example, a baby is born prematurely, and they are fed by tube rather than being able to breastfeed exclusively. If you choose to offer a bottle feed and breastfeed your newborn, they may take longer to breastfeed or bottle feed confidently as they learn both skills at the same time. 

Can You Mix Breast Milk and Formula? 

Short answer, yes. However, it’s important to mix breast milk and formula milk correctly so it is safe for your baby to drink.  

How to mix breast milk and formula 

1. Prepare the formula milk first. The guideline for most brands is one scoop per ounce of cool sterile water. Ensure you mix the correct quantity of water per measurement of formula powder/concentrated liquid.

2. If you are using ready-made formula milk, there is no extra formula prep to do at this point.

3. Add preferred ounces of breast milk to the prepared formula milk.

4. Mix well and serve at temperature, or warm gently in a jug of warm water or using a bottle warmer.

Note: if the breast milk you are using is frozen, you will need to thaw it completely before mixing it with the prepared formula and warming it. 

One Bottle or Alternate Feeds? 

This will come down to your personal preference. Some parents find that their baby prefers the taste of formula or breast milk, so combining the two means it gives them a chance to adjust to the taste gradually.  

Akshara, a combi-feeding mum, says “We chose combi feeding because it meant that our babies were getting all the nutritional benefits of breast milk, but the formula top-up meant it helped them to sleep for longer with less frequent waking during the night.” 

That being said, it’s important to note and be aware of the dangers of mix-feeding a baby and the precautions you must take. 

Risks and Precautions in Combination Feeding

Each mother and baby will experience a unique feeding journey, and sometimes it is dictated by limitations that either mum or baby have.  

For example, before you consider mix feeding your baby, check that they are not showing signs of allergies or digestive issues with either your breast milk or brand of formula milk. Some breastfeeding mums take it upon themselves to cut out certain foods and drinks so that their milk is safe for their babies to drink. 

Impact on Low Milk Supply 

Particularly if you have struggled to increase or maintain your breast milk supply, combi feeding can have an impact on your milk supply because you won’t be feeding at the breast or expressing breast milk as often. Breast milk production works on a supply-and-demand basis, and if the demand isn’t there, your milk supply will decrease.  

To maintain a healthy supply of breast milk for combination feeding, you can use an electric breast pump to efficiently express and encourage your supply to increase. Knowing which foods and/or drinks to avoid or eat more of will also help your body maintain your breast milk supply.  

How to Avoid Nipple Confusion in Combi Feeding 

Nipple confusion means your baby is feeding ineffectively as they transition from a baby bottle to the breast, and vice versa. Although some babies take longer to adapt to the transition than others, usually nipple confusion stems from other breastfeeding-related issues such as poor latch, nipple pain, or low milk production.  

When you introduce a bottle to a breastfed baby, it’s a slightly different skill set for them to apply - and that takes some practice! Not all baby bottle teats are shaped the same way as the breast, although some designs mimic this very well. You can also use nipple shields if this helps your baby to fluctuate between the two.  

Learn more: Best Bottles for Breastfed Babies

How to Start Combination Feeding 

Combination feeding comes in all shapes and sizes. From top-up formula feeds after breastfeeding, using formula feeds at night, or offering formula whilst you pump breast milk, they are all versions of combi feeding.  

How to Combine Breastfeeding and Formula Feeding 

To start with, pick one breastfeed during the day or night that you can swap for a bottle of formula. From there, you can introduce more bottles of formula throughout their schedule and use this time to give mum respite from breastfeeding, catching up on sleep, or spending time with older siblings. Some tips to get you started are: 

• Start with a feed where they are alert and content rather than tired and hungry, so they have the patience to persevere if they don’t take to it quickly! 

• Gradually add more formula to an expressed bottle of breast milk so your baby can get used to the different tastes. 

• Start by breastfeeding and then ask a partner or caregiver to give the top-up feed, allowing time for pumping or resting.  

Choosing the Best Baby Formula for Combination Feeding 

With so many formula brands on the market, it’s hard to say which is the best baby formula for combination feeding. However, when you choose the right formula for your baby, it will be because it is meeting their nutritional needs and they feel comfortable after a feed (e.g. no tummy discomfort, intolerance symptoms, etc.).  

How to Combine Breastfeeding and Pumping 

Using a single electric breast pump, you can breastfeed on one side and pump on the other. In doing this, you can offer both breasts to your baby if they are still hungry but also spend less time expressing after your baby has fed.  

Some breastfeeding mothers choose to express more at night because the consistency of their milk is different than during the day. It also means that you can pump whilst your partner can give a bottle feed.  

There is no right or wrong time to schedule breastfeeding and pumping sessions but it’s helpful to work it around your baby’s appetite so that if they are going to breastfeed, they are not working super hard to get milk from you if you have only just expressed. A hungry baby will want milk to be bountiful, so it’s helpful to bear this in mind! 

How to make a combination feeding routine 

There is no set combination feeding schedule, but you will find a rhythm and feeding routine that works for you as a family. To help you come up with an initial plan, ask yourself these questions: 

• Are you planning on returning to work soon? If yes, do you want to continue breastfeeding when you go back to work? 

• How often does your baby feed throughout the day? (This will vary depending on their age and development.) 

• What are the best times for you to breastfeed or pump? 

• Do you need to factor in more breast-pumping sessions to maintain your milk supply? 

• Are you a parent of multiples?  

• Are you going to alternate between breast milk and formula milk or mix the two? 

Combi Feeding Routine from Birth 

If you’re still unsure how to start combi feeding, you can try this combination feeding schedule and adapt it as you need to. This example combination feeding routine is for families who want to start combi feeding from birth.

1. Offer your baby breast milk at the breast (unless they are unable to, in which case, they will be tube fed or can be given expressed colostrum/breast milk through a syringe).

2. Continue to offer the breast for each feed. Gradually, offer a small top-up of formula milk in a bottle at each or every other feed.

The number of times you offer formula milk is up for you to decide.

a. Offer breast milk first thing in the morning and at bedtime and formula milk feeds during the day.

b. Offer breast milk during the day and formula feeds at night.

c. Offer expressed breast milk in a bottle and alternate this with formula milk throughout the day or mix the two.

3. Every 2-3 hours your newborn will need to be fed. Ensure you’re offering both breasts during a breastfeeding or pumping session. When your baby is being fed with formula milk, you can use this time to pump and build a breast milk stash for expressed bottle feeds.

4. Monitor how much milk your newborn is drinking and gauge their satisfaction and hunger levels after offering the breast first and after formula feeds.

The number of feeds will change as your baby gets older and goes through development milestones. When your baby starts to wean at 6 months, their combi feeding schedule will change again as you introduce new textures and flavours through solid foods. From a year old, you may be thinking about returning to work which will mean you rely more on expressed breast milk or cow's milk and step away from formula or mixed feeds. 

If you have concerns that they are not feeding enough, are losing weight, or not producing enough dirty or wet nappies, seek advice from your healthcare professional.  

How to Encourage a Breastfed Baby to Take a Bottle 

The most important thing to remember when offering a breastfed baby a bottle feed is to be patient. Bottle feeding for a breastfed baby can seem a little backward at first and out of their comfort zone, but with some help, they can soon feel comfortable and feed confidently to stop them from refusing it altogether.  

There are a few tips and strategies to get you started and to help your baby accept a bottle feed, especially if it is introduced later once breastfeeding has been established.  

• Dip the end of the bottle teat in breast milk or formula milk - it will help them to understand what is coming next.  

• Wear a muslin with your scent or try skin-to-skin to help your baby relax. 

• Use a slow flow teat and pace feed so they can control the speed at which they drink, similar to when they breastfeed. 

If your baby persistently refuses a bottle, it doesn’t necessarily mean you need to try a new type of bottle. You can try these solutions to help manage their expectations: 

• Try offering the breast first, and then unlatch to offer a bottle. 

• Depending on your baby’s age, you can also try offering expressed breast milk or mixed breast and formula milk in a cup.  

• Offer a bottle when your baby is content and alert so it reduces any stress on their part if they start refusing, or offer a bottle as soon as they have woken from a nap. A sleepy baby is sometimes more willing to try!  

Conclusion 

For parents wondering "can you mix formula and breastmilk?" or "should you mix formula and breastmilk?", the answer is yes—it can be a great way to balance nursing and bottle feeding. 

Combi feeding can be like experiencing the best of both worlds and the beauty of combination feeding is that you can adapt your feeding schedules to work for your baby and family, the way it works best.