Baby Feeding Central

You did it! You brought your baby into the world (amazing job, by the way) and you're starting to acclimate to this new life together. We know that it can all feel like a *lot*, so we pulled some of the world's best advice together to give you some perspective and confirm you've totally got this!

I want to make sure you know that there is a way for you both to not only survive but THRIVE. All the information out there can make it feel pretty overwhelming — but it doesn't have to be.

We put together a library of tips and tools to guide you on your unique baby feeding journey, whether you’re exclusively nursing, exclusively pumping, combo-feeding, or formula feeding. Choose the topics that interest you to learn more. And please, as always, reach out with ANY questions! We are a team of moms and lactation consultants that have been through it all.

  • Breastmilk Basics

    Breastmilk is powerful and so are you!

    The complex composition of breastmilk: It's liquid gold!

    Breastfeeding is good for you too, mom!

    The “do's and don’ts” of breastmilk storage

    Don't let breastmilk storage myths get you down!

    Navigating the Process

    How to safely store and transfer breastmilk

    Milk talk (part one) — Thawing and warming the easy way

    Milk talk (part two) — How to bottle-feed breastmilk or formula

    The truth about low milk supply

    Sterilizing, disinfecting, sanitizing, and fridge hacks…oh my!

    Special Circumstances

    Feeding your NICU baby

    What to do if you have high lipase breastmilk

    Feeding with Formula

    Formula 101 – Everything you need to know!

    Formula + breastmilk = combo feeding

    Beyond the Basics

    Milk donation 101: Formal and informal sharing

    The science of pooling milk

  • Breastmilk is powerful and so are you!

    When it comes to feeding our little ones, there's nothing quite like the liquid gold produced by their mothers. Breastmilk is a gift from nature, uniquely crafted to provide the optimal nutrition vital for growing infants. 

    The perfect blend

    A marvel of nature, your milk is perfectly tailored to meet the nutritional needs of your baby. Its precise combination of proteins, carbohydrates, fats, vitamins, and minerals is easily digestible, ensuring that babies receive the nourishment they need without straining their delicate systems.

    Immunological superpowers

    Breastmilk is not just food; it's a powerful shield against illness. It is packed with antibodies, immune cells, and other essential substances that boost a baby's immune system. These incredible components protect infants from a myriad of infections, reducing the risk of respiratory illnesses, ear infections, gastrointestinal issues, and even allergies. Breastfed babies enjoy a stronger defense against the world around them.

    Growth and development

    Breastmilk contains the ideal balance of nutrients that support healthy bone development, muscular growth, and brain function in infants. The fatty acids present in breastmilk, such as DHA (docosahexaenoic acid), play a crucial role in the development of the brain and nervous system, promoting optimal cognitive function and overall intelligence.

    Gut health and digestion

    The gut (some of us call it a tummy) is the epicenter of a baby's overall health, and breastmilk plays a vital role in nurturing a healthy digestive system. Breastmilk contains prebiotics and probiotics that promote the growth of beneficial gut bacteria. These friendly bacteria help establish a strong immune system, aid in digestion, and prevent gastrointestinal disturbances such as colic, constipation, and diarrhea.

    Nutrition unique to each baby

    One of the incredible aspects of breastmilk is its ability to adapt to a baby's changing needs. As the baby grows and develops, the composition of breastmilk adjusts to meet their specific requirements. For example, the amount of fat, protein, and antibodies in breastmilk changes to support the baby's growth spurts and provide additional protection against infections. It's a personalized nutrition plan that no formula can replicate.

    Bonding and emotional connection

    Breastfeeding is not only about nutrition; it's also a profound bonding experience between a mother and her baby. The skin-to-skin contact, the eye contact, and the release of hormones like oxytocin during breastfeeding foster a deep emotional connection. It provides comfort, security, and a sense of love and belonging for both mother and child.

    Reducing health risks

    Breastfeeding offers long-term health benefits for babies. Studies have shown that breastfed infants have a reduced risk of developing chronic conditions later in life, including obesity, type 2 diabetes, asthma, allergies, and certain types of cancers. By providing the best possible start in life through breastmilk, mothers can help safeguard their babies' health well into adulthood.

    Overall, breastmilk is a precious gift from nature that is uniquely designed to provide optimal nutrition for infants. Its exceptional blend of nutrients, immunological superpowers, and ability to support growth and development make it the ideal choice for feeding our babies. Breastfeeding not only nourishes their bodies but also strengthens the bond between mother and child. By understanding and embracing the importance of breastmilk, we can give our babies the best possible start in life, setting the stage for a healthy future.

  • The complex composition of breastmilk: It's liquid gold!

    Breastmilk is a remarkable fluid, designed to provide optimal nutrition and immunity for newborns. Its composition is a complex blend of various components, uniquely tailored to meet the specific needs of each growing infant. Understanding the intricacies of breastmilk composition sheds light on the remarkable benefits it offers.

    Here are five key components of breastmilk and their roles in promoting the healthy development of infants.

    1. Colostrum

    Colostrum is the initial fluid produced by breastfeeding mothers. Although it is produced in small quantities, it is packed with immune-protective factors such as secretory IgA, lactoferrin, and white blood cells. Colostrum also contains developmental factors like epidermal growth factor, crucial for the early growth and maturation of the infant.

    2. Macronutrient composition

    Breastmilk consists of macronutrients including protein, fat and carbohydrates. The overall macronutrient content remains consistent across different populations of women, irrespective of maternal nutritional status. 

    • Proteins in breastmilk include casein, α-lactalbumin, lactoferrin, secretory immunoglobulin IgA, lysozyme, and serum albumin. These proteins play vital roles in immune function and growth.

    • Fat is the most highly variable macronutrient of breastmilk. Its concentration is influenced by milk storage within the breast. The initial milk that flows during a feeding is lower in fat, while the milk obtained later in the feeding is higher in fat. Additionally, the fatty acid composition of breastmilk is influenced by maternal diet, particularly the consumption of long-chain polyunsaturated fatty acids (such as omega-3 fatty acids)

    • Lactose is the main carbohydrate in breastmilk. Oligosaccharides are another important carbohydrate in breastmilk. They promote the growth of beneficial bacteria in the infant's gut.

    3. Micronutrient composition

    The supply of vitamins and minerals in breastmilk is largely determined by the mother’s diet. Below are three generally recommended vitamins and minerals.

    • Vitamin B12: Vegan or vegetarian breastfeeding mothers may require supplementation due to potential deficiencies.

    • Vitamin D: Breastfed infants at risk of vitamin D deficiency include those with darker skin, mothers who lack vitamin D, and those with limited sunlight exposure.

    • Iodine: Pregnant and breastfeeding women are advised to take iodine supplementation to ensure sufficient concentrations in breastmilk.

    If you have questions about adding vitamins and minerals to your diet or about any specific medical conditions, always seek the advice of a physician or other qualified health care provider who can provide an individualized evaluation and treatment plan.

    4. Bioactive factors: Nurturing infant health and development 

    Breastmilk contains various bioactive factors including living cells, antibodies, cytokines, growth factors, oligosaccharides, and hormones. These components influence biological processes and contribute to infant health and development. Many of these factors work synergistically, and supplementation with individual components may not replicate the same benefits.

    Growth factors in breastmilk play significant roles in the development of the infant's gut, blood vessels, nervous system, and endocrine system.

    5. Anti-infective factors

    Breastmilk is rich in anti-infective factors that help protect against infections and inflammation. It contains white blood cells, secretory IgA antibodies, lysozyme, lactoferrin, and other proteins that contribute to the infant's immune defense.

    • Oligosaccharides in breastmilk act as prebiotics, selectively promoting the growth of beneficial bacteria in the infant's gut. These oligosaccharides also act as decoys, preventing pathogens from crossing the gut wall and causing illness.

    • Furthermore, breastmilk contains its own microbial community, which contributes to the development of the infant's gut microbiome. Oligosaccharides influence the bacterial composition of breastmilk, further supporting the establishment of a healthy gut microbiota.

    Overall, breastmilk is a remarkable and ever-changing fluid that provides infants with the optimal nutrition and immunity they need for healthy growth and development. Its composition includes macronutrients, micronutrients, bioactive factors, and anti-infective components. Breastmilk's complex composition highlights the importance of breastfeeding as the biological norm for infants, offering unique benefits that cannot be replicated by any substitute and reinforcing the significance of supporting and promoting breastfeeding as the gold standard for infant feeding.

  • Breastfeeding is good for you too, mom!

    Breastfeeding is one of nature's superpowers, offering incredible advantages for both mothers and their babies. It's a beautiful, intimate experience that provides not just nourishment, but so much more. Let’s explore the amazing benefits of breastfeeding and why it's such a gift for both mothers and their little ones.


    1. Supercharged nutrition
      Breastmilk is a powerhouse of essential nutrients, perfectly designed for babies. It contains a magical blend of proteins, fats, and carbohydrates that promote healthy growth and development. Breastfed babies receive the ideal balance of nutrients to support their rapidly evolving needs.

    2. Immune boosting wonder
      Breastmilk is a superhero when it comes to helping babies fight off illnesses and infections. It's brimming with antibodies and immune-boosting substances that provide protection from a wide range of diseases. Breastfed infants are less likely to suffer from respiratory infections, ear infections, tummy troubles, and even chronic conditions down the road.

    3. Gentle on tiny tummies
      One of the remarkable benefits of breastmilk is that it's gentle on delicate digestive systems. Breastfed babies experience fewer tummy woes, like constipation and diarrhea. The probiotics found in breastmilk promote the growth of healthy gut bacteria, reducing the risk of colic and upset stomachs.

    4. Brainpower booster
      Breastfeeding gives babies an intellectual edge. Research has shown that breastfed infants tend to have better cognitive development, higher IQ scores, and improved language skills compared to those who are formula-fed. Special fatty acids like DHA (docosahexaenoic acid) that are present in breastmilk play a key role in brain development.

    5. Shield against future health woes
      Breastfeeding sets the stage for a healthier future. Breastfed babies have a reduced risk of developing obesity, type 2 diabetes, asthma, allergies, and certain types of cancers like leukemia and lymphoma. This gift of nutrition in their early days can have a lasting impact on their well-being.


    1. A bond like no other
      Breastfeeding creates an unbreakable bond between mother and child. The skin-to-skin contact and the release of oxytocin, known as the love hormone, during breastfeeding foster feelings of love, closeness, and well-being. It's a beautiful experience that deepens the connection between mother and baby.

    2. A postpartum recovery boost
      Breastfeeding jumpstarts the body's healing process after childbirth. The hormones released during breastfeeding help the uterus contract, reducing postpartum bleeding and aiding in a quicker recovery. What's more, breastfeeding burns extra calories, which can assist in shedding pregnancy weight.

    3. A shield against postpartum blues
      Mothers who breastfeed often have a reduced risk of postpartum depression. The release of oxytocin during breastfeeding promotes relaxation, emotional well-being, and a sense of calm. It's a natural anti-depressant, providing a shield against the baby blues.

    4. Long-term health benefits
      Breastfeeding contributes to a mother's long-term health and well-being. It lowers the risk of breast and ovarian cancers, osteoporosis, and cardiovascular diseases such as heart attacks and strokes. The more a woman breastfeeds throughout her life, the greater the protective effect.

    5. Convenience and cost savings
      Breastfeeding is the epitome of convenience. No bottles to sterilize, no formula to mix, and no worries about running out of supplies. Breastmilk is always available, making it an economical choice for families. It saves time, money, and makes life a little simpler.

    From providing optimal nutrition, boosting immunity, and promoting cognitive development in babies to giving moms an intimate and emotional bond, quicker postpartum recovery, and long-term health advantages, breastfeeding is a remarkable gift from nature. By understanding and supporting the benefits of breastfeeding, we can contribute to the well-being and future health of children and mothers worldwide.

  • The “do’s and don’ts” of breastmilk storage

    To make sure that our liquid gold is safe and healthy for our babies to drink, proper storage is essential. It’s the best way to maintain breastmilk’s incredible properties and nutrients. Navigating the world of breastmilk storage can feel overwhelming, with all the rules and regulations, but we promise, it does get easier!

    To kickstart your breastmilk storage education, here are some helpful guidelines.

    First, a few general rules from the CDC to ensure that your pumping environment and gear are clean:

    • Wash your hands well with soap and water. If soap and water aren’t available, use an alcohol-based hand sanitizer.
    • If using a pump, inspect the pump kit and tubing to make sure they are clean. Discard and replace moldy tubing immediately.
    • If using a shared pump, clean pump dials, power switch, and countertop with a disinfectant wipe.

    After expressing your milk, there are a number of ways to safely store it. The storage temperature depends on how long ago the milk was expressed.

    Storage Guidelines

    • In the Ceres Chill Breastmilk Chiller or a cooler (59° F and below): Protocol #8 from The Academy of Breastfeeding Medicine states that breastmilk can be kept at 59° F or less for up to 24 hours, and our Chiller will keep your milk below that temperature for that amount of time. If you’re using a cooler, the length of storage time might be less depending on how quickly the ice packs lose their chill, but you should usually still be able to get about 6-8 hours out of them.
    • At room temp (66° F - 78° F): Ideally, milk should be kept at room temperature for up to 4 hours. However, if necessary and if pumped in a clean environment, it can be stored at room temp for up to 8 hours before being transferred to a chilling device.
    • In the fridge (below 41° F): 3 days is ideal, but 5-8 days is acceptable and safe.
    • In the freezer (below 4° F): Up to 6 months is best, up to 12 months is acceptable. Be sure to label your milk with the date of expression!

    Storage Containers

    You have options when it comes to storing your breastmilk – some good, some not so good.

    Fridge & Short-Term Storage

    Stainless steel containers

    PROS: A great non-plastic alternative that is shatterproof and made with antibacterial materials.

    CONS: Thinner stainless steel bottles do not do well in the freezer.

    Glass containers

    PROS: Good for fridge and freezer storage. Will not leach chemicals into your breastmilk. 

    CONS: Not shatterproof and will break easily if dropped.

    🚫 Plastic freezer bags

    PROS: Affordable up front 

    CONS: Expensive over time because you have to keep purchasing them. Disposable and wasteful, these single use bags end up in landfills. 

    Long-Term Freezer Storage

    Silicone cubed containers (check out the Ceres Chill Milkstache Trays!)

    PROS: Freeze milk in perfect proportions for easy defrosting. Take up less space in the freezer than dozens of bags. Cubes can be transferred to silicone bags once fully frozen, and the cubed trays can continue to be filled when you’re ready to make more!

    CONS: None!

    Silicone bags

    PROS: Easy to use, easy to clean and BPA-free, these are a great alternative to disposable bags.

    CONS: Can be expensive to buy a lot if storing a large amount of milk

    🚫 Plastic containers

    PROS: Durable and usually the most affordable option.

    CONS: Some plastic storage containers leach chemicals like BPA (bisphenol A) and phthalates into breastmilk. While most companies now produce BPA-free breastmilk storage containers, there still isn’t enough research into the effects of other chemicals found in plastic.

    Pooling Milk (The Pitcher Method)

    Pooling breastmilk, which is the process of combining freshly pumped milk with previously pumped milk, is an easy and safe way to mix milk from different pump sessions! Many moms do this if they have multiple bottles of milk from different sessions, but each bottle is not enough for a full feeding. By combining that milk, you have enough for full feedings AND you have more evenly distributed nutrients.

    Based on recently published research, pooling breastmilk over the course of a day is beneficial. Pooled breastmilk provides evenly distributed caloric feedings, is more convenient for new mothers, and is believed to decrease the risk of contamination that results from multiple containers. The study specifically showed no signs of increased bacteria from combining newly expressed milk with chilled milk from multiple pumping sessions over 24 hours.

    You can also pool breastmilk from different days, as long as you use the oldest date of expression when determining how long that milk is good for. If you’re combining milk from 2 days ago with milk from today, you would date all the milk as two days old.

    There you have it — all the breastmilk storage basics. Feel free to reach out to us anytime with questions!

  • Don't Let Breastmilk Storage Myths Get You Down!

    If there’s one thing we hate, it’s outdated advice and recommendations with no scientific basis. New parents already have so much to learn, and with conflicting information all over the place, it’s really hard to know where to start!

    We’re going to air some harmful breastmilk storage myths that you might have seen online, so you know not to spend even one minute stressing about them and wondering if you’re doing something wrong. Because in all likelihood…you’re not!

    Myth: You Can't Shake Breastmilk
    It was once believed that shaking your breastmilk would break down the protein molecules in it, which would then affect the nutritional value of your milk. Turns out, there is absolutely no published evidence to support this claim!

    Breastmilk is incredibly strong, and while shaking it may change its physical appearance, it will not damage your milk! It would take much more than a little shake to damage a protein. You would need to be super strong. Like…Hulk-level strong.

    Myth: Pooling Milk Is Dangerous
    Based on published research, pooling breastmilk (you might have heard it called the Pitcher Method) over the course of a day is safe and beneficial. Pooled breastmilk provides evenly distributed caloric feedings, is more convenient for new mothers, and is believed to decrease the risk of contamination that results from multiple containers. Studies specifically showed no signs of increased bacteria from combining newly expressed milk with chilled milk from multiple pumping sessions over 24 hours.

    You can even pool milk from different days if you date the milk using the oldest date of expression!

    Myth: Breastfeeding Comes Naturally
    It’s true that our bodies were born to do this — we do have boobs for a reason. It’s also true that our babies are born with rooting, suckling and swallowing reflexes that help to kickstart the breastfeeding journey.

    BUT, that doesn’t mean that it’s easy or that it will be a smooth process from the beginning. Breastfeeding is a skill — a truly amazing one — and it has to be practiced by mom and baby. It can be a loving and bonding experience that is also filled will tears and worries.

    In a perfect world, we would just put our babies to our breasts and they would latch right on. All would be good! But that doesn’t always happen immediately. You aren’t expected to get it perfect. Sometimes we need a little bit of extra help, and that’s more than okay.

    Myth: Breastmilk Is Fragile
    Breastmilk is actually incredibly destructive in the best possible way. It has epic antibacterial and antimicrobial properties that help to fight and destroy harmful bacteria. Human milk is a living substance that can withstand a lot!

    Myth: You Need to Clean All Your Gear Daily
    The FDA states that while it’s not possible to fully sterilize pump parts at home, dishwashing soap and warm water will do just fine:

    “All breast pump parts that come in contact with breast milk, such as bottles, valves and breast shields, should be cleaned after each use. It is not possible to completely sterilize breast pump parts at home, even if you boil them. However, sterilization is not necessary to keep these parts safe and sanitary. You can do that by thoroughly washing away germs and bacteria with liquid dishwashing soap and warm water.”

    For a healthy, full-term older baby, it is not necessary to fully sterilize your parts every day. The exception to this is if your baby is less than three months old, currently ill, or born prematurely. In that case, the CDC recommends that you sterilize all of your breastfeeding gear at least once a day.

    Myth: If You Only Breastfed for a Few Months, It Didn't Do Much
    Definitely not true! One drop of breastmilk contains over one million germ-fighting cells. Every single bit of milk you make is worth it. You're giving your baby the best possible start to life, whether you breastfeed for one month or one year.

    Do your best. No shame and no judgment. Every drop, every ounce — it’s all worth it and you are doing an amazing job. You got this, and we at Ceres Chill are ALWAYS here to support you!

  • How to safely store and transfer breastmilk

    After you’ve finished pumping your breastmilk, you can maintain its many nutritional properties and avoid contamination by storing it in the proper containers. This liquid gold fuels your baby, so knowing how to keep it as safe as possible is super important. Let’s get into it!

    Storage Containers

    You have options when it comes to storing your breastmilk — some good, some not so good.

    Fridge and short-term freezer storage

    ⭐ Stainless steel containers

    PROS: A great non-plastic alternative that is shatterproof and made with antibacterial materials.

    CONS: Thinner stainless steel bottles do not do well in the freezer.

    ⭐ Glass containers

    PROS: Good for fridge and freezer storage. Will not leach chemicals into your breastmilk. 

    CONS: Not shatterproof and will break easily if dropped.
    🚫 Plastic freezer bags

    PROS: Affordable up front 

    CONS: Expensive over time because you have to keep purchasing them. Disposable and wasteful, these single use bags end up in landfills. 

    Long-term freezer storage

    ⭐ Silicone cubed containers (check out the Ceres Chill Milkstache trays!)

    PROS: Freeze milk in perfect proportions for easy defrosting. Take up less space in the freezer than dozens of bags. Cubes can be transferred to silicone bags once fully frozen, and the cubed trays can continue to be filled when you’re ready to make more!

    CONS: None!

    ⭐ Silicone bags

    PROS: Easy to use, easy to clean and BPA-free, these are a great alternative to disposable bags.

    CONS: Can be expensive to buy a lot if storing a large amount of milk

    🚫 Plastic containers

    PROS: Durable and usually the most affordable option. 

    CONS: Some plastic storage containers leach chemicals like BPA (bisphenol A) and phthalates into breastmilk. While most companies now produce BPA-free breastmilk storage containers, there still isn’t enough research into the effects of other chemicals found in plastic.

    Proper Labeling & Dating

    When labeling breastmilk, write the date of expression on the container. If your baby goes to daycare, it might also be good to label the milk with their name.

    It’s important to note that the composition of your breastmilk constantly changes to suit the needs of your baby. There are some special circumstances in which you might need to include extra information on your milk bags to know when to use them. 

    For example, if you are breastfeeding and pumping and your baby comes down with a cold or a virus, it’s good to note that on your milk bags. The milk that you produce during this time could speed up their recovery.

    Amazingly, the composition of your breastmilk changes when your baby is ill. If you’re exposed to a bacterial or viral infection, your body makes antibodies to combat it; these are then transferred to your baby through your milk. The levels of immunity-boosting cells, called leukocytes, in your milk also rise rapidly whenever your baby is unwell.
    — Medela, The Science of Care

    You can also choose to include the time of day that the milk was collected. Levels of cortisol are three times higher in milk that was pumped in the morning versus milk that was pumped at night, while melatonin levels rise in the evening and peak at midnight. 

    This means that our milk helps provide time-of-day information to our babies. Researchers suspect that “mistimed milk” might interfere with the development of a baby’s circadian rhythms, so if you feel that your baby is experiencing sleep troubles, try giving them the milk that was expressed at certain times of the day!

    Transferring Breastmilk to Different Containers

    To avoid spills or messes, it’s important to be super careful when transferring breastmilk from your collection container into a different container.

    When transferring your milk to bags, use a funnel if your bottle doesn’t have a narrow neck. If you’re pouring milk from the Ceres Chill Breastmilk Chiller outer chamber, be sure to keep your connector screwed on to give you a smaller opening and more control. 

    If you’re transferring milk from bottle to bottle to combine for a fuller feed, using something like the bökee, a hands-free baby bottle holder that is great for keeping one bottle secure while you pour into another.

    Avoiding Contamination

    To keep your milk as safe and fresh as possible and avoid contamination, be sure to work the following tips into your routine:

    • Wash your hands and pump parts before starting your session.
    • Clean the pump parts in between sessions, either by using our portable washbasin bag, and pump wipes, or cleaning sprays. You can also use this fridge hack: store your pump parts in a gallon-size zip-top bag in the fridge and just wash them every few sessions. (It is important to note that this is not a CDC-approved method of keeping parts clean throughout the day.)
    • Always be sure to thoroughly clean your parts. Only wash your pump parts with your other pumping gear in a separate container or washbasin. Don’t wash them in the sink with the rest of your dishes!
    • Be sure to keep all storage containers clean and sealed.
    • Store your milk at the correct temperature

    Overall: Breastmilk is incredibly strong and can withstand a lot, but following these guidelines is really important to make sure that you’re giving your baby the safest milk you can. If you ever suspect that your milk has been contaminated or gone bad, do a taste and smell test to be sure. If it smells or tastes sour or ‘off’ in some way, you can still freeze that milk for future milk baths or topical uses!

    More Information

  • Milk talk (part one) — Thawing and warming the easy way

    Let’s talk about the best way to defrost breastmilk and warm baby bottles.

    First, here are some general guidelines on thawing and warming breastmilk from the CDC:

    • First in, first out: Always thaw the oldest breastmilk first.
    • Once breastmilk is brought to room temperature or warmed, use it within 2 hours.
    • Never refreeze breastmilk after it has thawed.
    • Never thaw or heat breastmilk in a microwave. Microwaving can destroy nutrients in breastmilk and create hot spots which can burn a baby’s mouth.

    Exclusive Pumping


    In the fridge: Slowest but most preferred

    This is the preferred way to thaw because it causes less fat loss compared to other thawing methods. Because the length of defrosting time depends on several different factors, it’s best to take the milk out of the freezer and put it in the fridge about 12-24 hours before you need it. Be sure to use that milk within 24 hours of it being completely thawed (meaning no more ice crystals).

    In a container of warm/lukewarm water: Best for immediate use

    If you’re warming a bag for your baby to drink ASAP, thawing in a bowl of warm water is the quickest way to do it. Remember that once the milk has been warmed, it should be used within 2 hours, so it’s best to only use this method if you’re using the entire bag of milk. All you would do is fill a bowl with warm water and pop the bag in. Wait a few minutes for it to fully defrost, and then pour it into a bottle!

    A great alternative to bags and wasted milk is our Milkstache, which allows you to freeze milk in perfect ½ ounce quantities. Instead of defrosting an entire bag and wasting extra milk if your baby doesn’t drink it all, you only need to defrost the exact amount you need. Check out this cool tutorial.

    In a bowl of cold water: Best for using some now, and saving some for later

    If you’ll only be using a portion of the milk in the bag right away, this is a great method to use. You can fill a bowl with cold water, add your milk in, and wait for it to thaw out. Once it’s thawed, you can store it in the fridge for prepping bottles later. Since all that milk will still be cold, it does not need to be used within two hours. This milk would be good for the next 24 hours, similar to the guidelines when defrosting in the fridge.


    That's right, Ceres Chill's Breastmilk Chiller can also be used to warm milk. Here is the step-by-step process from our product guide:

    Chiller Image Chiller Image


  • Milk talk (part two) — How to bottle-feed breastmilk or formula

    Ready to start bottle feeding your baby? It’s a learning process for both of you so here are some tips for introducing a bottle and setting your little one up for success. (Remember – while newborn babies commonly have 6-8 feeds every 24 hours and 8 - 12 feeds is the goal, there’s no set amount of food or number of feeds your baby SHOULD have, so just feed your baby when they are hungry.)

    • When first introducing a bottle, be sure to pick a time when your baby is not too hungry or full. It’s easier to introduce new things when they're calm and comfortable. 
    • Be sure to test the flow of the milk or formula from the bottle. It should be a steady drip, but not a flow. A slow flow nipple is preferred.
    • Cuddle your baby close, in a sitting position, when feeding from the bottle.
    • Position the bottle at a horizontal or parallel angle to the ground so that the milk only comes out when your baby sucks, letting the baby control the flow. 
    • Offer them small amounts at first and let them take a break when it seems like they need one.
    • Stop feeding from the bottle when your baby seems full, even if the bottle isn’t empty. Don’t force them to finish the bottle.


    • Feed the baby when their cues indicate hunger, rather than on a schedule.
    • When feeding, hold the baby in an upright position. It’s also best to hold a baby at other times than when being fed, so as not to train the baby that they must eat in order to be held.
    • Switch from one side to the other midway through a feeding to provide for eye stimulation and to overcome a side preference.
    • Feed the baby for 10-20 minutes at a time. Try to make appropriate quantities last that length of time. This allows the baby to recognize when they are full.
    • Begin feeding by gently allowing the infant to draw the nipple into his mouth rather than pushing the nipple into the infant’s mouth.
    • Stroke baby’s lips from top to bottom with the nipple to elicit a rooting response of a wide-open mouth and then allow the baby to ‘accept’ the nipple rather than poke it in.
    • Consistent with a breastfed rhythm, the caregiver should encourage frequent pauses while the baby drinks from the bottle to mimic the breastfeeding mother’s let-down patterns. This discourages the baby from guzzling the bottle and can mitigate the nipple confusion or preference.
    • Only feed the baby until the baby is full; don’t encourage the baby to finish a bottle. If the baby is dozing off and releasing the bottle nipple before the bottle is empty, that means the baby has had enough. Don’t reawaken the baby to finish it!


  • The truth about low milk supply

    There are legitimate clinical explanations for low milk supply, like breast or chest surgery, trauma to the chest or breast area, anatomical differences, or even hormonal or endocrinology disorder. These specific issues need to be assessed by a lactation consultant or IBCLC to determine if they are causing low milk supply so you can set and meet your breastfeeding goals. 

    There are also many ways society judges milk production that are not true signs of low milk supply. Most women produce just the right amount of milk that their babies need. Unfortunately, a lot of women still believe they are not making enough thanks to the mistaken opinions of social media and well-meaning family and friends. 

    Your body is uniquely wired to create breastmilk that targets the specific needs of your child. You’ve probably heard that one way to check your supply is to pump. While in theory this makes sense because you can “see” how much milk baby is getting, it’s not accurate for a number of reasons:

    1. Baby’s mouth is designed specifically for breastfeeding, so they get more milk out than a plastic pump can. 
    2. Since a pump removes milk differently than a baby does, our bodies sometimes have a harder time responding to the pump. In fact, some women don’t respond at all. For those women, they might get little to no milk out when they pump but are successfully able to exclusively feed from the breast for as long as they choose to breastfeed. 
    3. You might see on social media posts from moms or parents who are pumping 10+ ounces at a time, while your output is much less than that when the average output in place of a nursing session is 2-3 ounces combined. Take those posts with a grain of salt! 
    4. You were told by a well-meaning family member that babies should only eat every 4 hours and it seems like your baby is eating every hour, so that must mean your milk supply has gone down, right? No! Every woman has different milk storage capacity. Similar to how we all come in different sizes and shapes, so do our breasts. Some breasts might have smaller storage capacity and baby will need to feed more often. But rest assured, it is extremely normal and expected for your little one to breastfeed at least every 2-3 hours and then go through growth spurts and phases where they will eat more often. Those frequent feeds in a short amount of time are called clusterfeeding. Totally normal and good for your supply! 
    5. In an ideal world, all babies would nurse perfectly, sleep well, and be content in between. Thankfully we live in an exciting world where all babies are different and they all have their own unique personality, including being fussy!Having a fussy baby doesn’t necessarily mean you have low supply. Sometimes babies are fussy because they need a diaper change, a change of scenery, a cuddle, or they are too hot or too cold. Sometimes a fussy baby is just fussing to be fussy! 6. Engorgement or feeling full and having leaking breasts is also a sign that many women use to “feel” if their supply is where it needs to be, but leaking is actually NOT an indicator of supply.Our body makes milk on a supply versus demand system– the less often we remove milk and just wait for that full feeling, the less milk you will make. Think of your breast as a river or ocean instead of a gas tank. It is never empty, but when the water rises it will overflow. We want to avoid this feeling because it actually stimulates your body to make less milk. Some women will never leak and some women leak until they are well past a year of breastfeeding... it’s unique to every person! 

    Thanks to these common misperceptions, many women assume that they are “low producers” and start to make changes to produce more or supplement what the baby gets. Often women have misdiagnosed their production and take steps to remedy the situation, but these steps can lead to conditions that create low production, making it a self-fulfilling prophecy. Often, if there’s a dip in your supply, it is a temporary issue that your body will remedy on its own. 

    If you are concerned about your milk supply, the best way to determine the reality of the situation is to contact a lactation consultant. While family, friends or even strangers on the internet may have advice about your milk production, they are unlikely to have specific training in lactation. Get the best advice you can from the best advisor you can and sleep easier. Your body is doing exactly what your baby needs!

    Signs That Breastfeeding Is Going Well and That Baby Has Enough Milk

    • You are experiencing no pain with latching, and your nipples are not bleeding or cracked. 
    • Baby is nursing at least 8-10 times in a 24-hour period, and nursing at least every 2-3 hours.  
    • Baby is gaining weight on their own growth curve. 
    • Baby is having at least 6 wet diapers in a 24-hour period. 
    • Baby is meeting or exceeding their developmental milestones. 

    Of course, if you or baby are having any issues with breastfeeding, please seek out a lactation consultant near you and talk to your pediatrician. 

  • Sterilizing, disinfecting, sanitizing, and fridge hacks…oh my!

    Keeping our breastfeeding gear clean is important, but it can be super challenging and confusing when you’re away from home. We keep getting this same question: what exactly is “clean”? This question leads to follow-up questions like have I done “enough” to keep me and my baby healthy? Do I need to invest in a sterilizer or is soap and warm water enough? What is the “fridge hack”? Is it safe?

    All of it can feel like…a lot. Some people’s idea of perfection is not easy to maintain when you're at work, traveling or even just trying to survive at home. But perfection is not necessary. This part of the process is manageable.

    When cleaning your parts, you want to make sure to keep them separate from other dishes or non-breastfeeding items in the sink to prevent everything from getting dirtier with food, grease or bacteria. You may also want to use a special soap for baby items that is fragrance/dye free and can break up grease. Using a scrub brush that fits into pump part nooks and crannies and hasn’t been used to clean anything other than your baby bottles, nipple shields, flanges and tubing is a must. All of the other rules and extra stuff can be really overwhelming.  

    So, what’s a mom to do? Don’t stress! We’ve got everything you need to know right here.


    Sterilizing is making something free of bacteria and all living microorganisms. There are several ways to sterilize your pump parts:

    • A steam/heat sterilizer — works to kill bacteria by exposing the parts to saturated steam under pressure. 
    • A UV sterilizer — uses ultraviolet germicidal irradiation to break down certain chemical bonds that cause a microorganism to be unable to multiply.
    • Cold sterilization — submerging your pump parts in a bucket of cold water with a sterilizing tablet or solution for 30 minutes. 

    Disinfecting is a bit different than completely sterilizing. While sterilizing destroys all microorganisms, disinfection/sanitizing eliminates or removes harmful microorganisms from inanimate objects and surfaces. You can disinfect your pump parts by boiling them in hot water for one to five minutes or using sanitizing sprays.


    While this may already seem pretty overwhelming, there’s some good news: you don’t NEED to boil your pump parts every day or submerge them in a solution for 30 minutes. The most important thing is to make sure that your parts are clean and uncontaminated. 

    Cleaning works by using soap and water to physically remove germs from surfaces. This process does not necessarily kill germs, but by removing them, it lowers their numbers and the risk of spreading infection.

    To make sure that your parts are clean, inspect your entire kit to check for mold or old milk droplets before use — pump tubing can be extra tricky to clean, so if you notice that it’s moldy or soiled, it’s best to replace it.

    After you pump, thoroughly washing your parts with warm water and soap in a washbasin is sufficient to keep everything clean on the daily. You can also clean your parts in the dishwasher if it's recommended by your pump manufacturer. Allow the parts to air-dry, and then you’re all set! 

    You can also use cleaning wipes (like these amazing Bella B wipes) for a quick and easy cleaning!


    For a healthy, full-term older baby, it is not necessary to fully sterilize your parts every day, but cleaning your parts every day is extremely important. 

    The exception to this is if your baby is less than three months old, currently ill, or born prematurely. In that case, the CDC recommends that you sterilize all your breastfeeding gear at least once a day.


    The CDC breast pump cleaning recommendations are as follows:

    Before pumping, wash your hands thoroughly, inspect your pump kit and tubing to make sure that it’s clean, and clean (wipe down) your pumping area. After pumping …

    • Disassemble your pump tubing and all parts that come in contact with your breast/breastmilk (flanges, valves, membranes, connectors and milk collection bottles)
    • Rinse your pump kit to remove any remaining milk
    • As soon as possible after use, clean all of the pump parts that were in contact with your breast/breastmilk. 

    For cleaning by hand, the CDC recommends the same methods above - use a washbasin, add soap and water, scrub, rinse and dry, or place your parts in the dishwasher. After you’re done, clean your washbasin and bottle brush.

    For extra germ removal, the CDC states that you can sanitize your pump kit by using a microwave or plug-in steam system, or by boiling them and allowing them to air-dry. 


    The FDA states that while it’s not possible to sterilize pump parts at home, dishwashing soap and warm water will do just fine:

    “All breast pump parts that come in contact with breast milk, such as bottles, valves and breast shields, should be cleaned after each use. It is not possible to completely sterilize breast pump parts at home, even if you boil them. However, sterilization is not necessary to keep these parts safe and sanitary. You can do that by thoroughly washing away germs and bacteria with liquid dishwashing soap and warm water.”


    All of the parts do fit in sterilizers, but over time, the high heat and intensity can be hard on them and any of your breastfeeding gear. UV sterilizers can also affect the integrity of the plastic parts by breaking the bonds in them. 

    The best way to clean all of your Chiller parts is to wash them with warm water and dish soap. Sanitizing wipes and cold sanitizing work perfectly for all Chiller parts as well. But there are options if you want to take extra steps.

    Outer Chamber

    You should always hand wash the outer chamber to keep it looking as beautiful as ever, but you can fill it with boiling water as another cleaning measure. 

    Inner Chamber

    The inner chamber can go right on the top rack of the dishwasher or be placed in boiling water. Immersing it in boiling water is not necessary per the FDA guidance, but it can be done if you want to take that extra step. We do not recommend actively boiling it for sustained periods. 

    Plastic parts

    It's best to avoid boiling the plastic parts - instead, they can go on the top rack of the dishwasher with the inner chamber! 

    Try washbasin bags

    Another option for disinfecting your pump parts, Chiller parts, baby bottles and more away from home: a portable, water-resistant washbasin like the All-You-Need Washbasin Bag. Before leaving for your trip or workday, the only prep needed is to fill the easy-squeeze soap dispenser with your favorite baby soap.


    If you don’t have a convenient way to clean your pump parts on-the-go, you can choose to use the fridge hack — just pop your parts in a resealable bag like the boob bag) and stick them in the fridge between sessions! This works to ensure that the milk droplets on them don’t spoil and won’t be contaminated. Be sure to wash all of your parts thoroughly when you get home. This method is great for full-term babies — if you have a newborn/preemie baby, speak with your pediatrician or read up on the CDC guidelines for safe practices.


    Cleaning your pump parts daily is essential for the health and well-being of your baby, but it is not necessary to completely sanitize your parts every day, unless your little one is less than 3 months old, born prematurely or currently ill. Using a separate washbasin with warm water and dish soap is perfect for everyday cleaning. 

    Getting used to pumping and all the “rules” that come with it definitely takes some time, but we don’t have to over-complicate things for ourselves. With all of the above information, you’ll be able to pump and clean your parts with confidence. You got this, Mama! 

  • Feeding your NICU baby

    How to safely navigate breastfeeding when your baby’s birth didn’t go as planned

    The heroic staffers of the Neonatal Intensive Care Unit (NICU) care for the most vulnerable of humans – premature babies, babies with congenital concerns, and those struggling to transition from the comfy womb to our bright world. As the parent of a baby in the NICU, you are faced with many unexpected challenges but breastfeeding doesn’t need to be one of them!

    Breastmilk protects your NICU baby from NEC

    Necrotizing Enterocolitis or NEC is an intestinal disease that can affect premature and medically fragile infants in the NICU. While breastmilk doesn’t eliminate NEC, it does provide very good protection, with some studies saying it can lower the chances of NEC by almost half! According to the NEC Society, “For medically fragile babies, breastmilk is like medicine. Breastmilk – especially mother’s own milk – is critical to a baby’s healthy growth and development.”

    Breastmilk is best for NICU babies . . .

    Starting at around 16 weeks gestation until the first few days after giving birth, your body is making colostrum, otherwise known as liquid gold. Colostrum is a thicker, sometimes yellow substance that is the best part of breastmilk. It is very high in protein and low in fat and sugar, but most importantly it is full of antibodies which help protect against all kinds of viruses and bacteria. When your baby is born prematurely, it changes the composition of milk but premature milk is higher in protein and minerals, which is the best thing for a baby born prematurely!

    . . . Just follow these storage guidelines

    While we know that breastmilk is the best protective factor for all babies, the storage guidelines are much stricter for little ones in the NICU. You should start pumping somewhere around 6 hours after giving birth. If you don’t see much or anything using an electric pump in the hospital that early after giving birth, it’s okay! 

    To safely prepare breastmilk for your NICU baby, make sure to handwash before touching your pump parts or breastmilk. Also, sanitize your breast pump per the manufacturer's requirements. Each manufacturer will have specific cleaning and sanitizing recommendations, so be sure to follow what your pump specifies.  

    Hand expression vs. electric pumping

    The first few days after birth, you might have more success with hand expression versus an electric pump. Hand expression is a great way to get the colostrum moving and stimulate milk removal. Starting to use a hospital grade electric pump will also help stimulate milk removal as well, but you might not see much since colostrum is such a thick substance, which is okay and good for baby — it’s liquid gold!

    We want to simulate breastfeeding as much as possible, so make sure to pump every 2-3 hours for the first few weeks until your milk supply has been established. Don’t go longer than one 4-5 hour break each day.  

    Make sure to store your milk based on NICU rules. A lot of NICUs will request you put the date, time, and your name and date of birth on the bag or bottle to specify that it is your milk. They will store it at the NICU and will provide it to baby when you are not able to be there.  

    What is the goal of pumping? 

    By pumping regularly, your milk will come in and a robust milk supply will be made. The more milk you can pump in the first few weeks, the better the chance that you will have a full milk supply when your baby is discharged. Goal output by the end of the second week is about 16 ounces a day. The first day or so, you might not get more than drops and then a few mLs/CCs. The more consistent you are with milk removal, the faster you will see the milk start to increase and change from colostrum to transitional milk to mature milk. 

    A few more tips for your NICU stay

    • The Ceres Chill Breastmilk Chiller is a great way to store milk on the go. With the benefit of directly pumping into the Chiller and keeping your milk cold without a fridge or cooler, it’s one less stress on you and your family during this emotionally challenging time. 

    • Skin-to-skin care, or kangaroo care, is shown to be beneficial for stability and optimal growth and development of premature babies. Breastmilk pumping, or expression, immediately after holding your baby skin-to-skin is a very effective way to increase your milk supply. Some mothers find pumping at their baby's bedside in the NICU very helpful, as well.

    • Self-care for parents is a MUST. Having a baby in the NICU can be a hard journey for many parents, so find a NICU parents support group near you. And lean on your NICU nurses – they are part of your care team and angels in this world for both you and your baby. You are always able to call to check on your little one, and the nursing staff will help you learn how to care for your baby.  

    And most importantly of all, know that you are the perfect mom for your perfect baby!

  • What to Do If You Have High Lipase Breastmilk

    High Lipase breastmilk is a reality for many moms who don’t realize it until they return to work. You didn’t have any significant issues with your breastmilk while nursing at home but once you committed to pumping and storing your milk, a problem arises. You get home with your daily stash and store your milk in the fridge, only to notice an odd odor when you take it out the next day. The smell is soapy, metallic, fishy, or sour. You think it might be spoiled, but after doing some research, you discover that you may have High Lipase breastmilk.

    Lipase is an enzyme that’s naturally found in all breastmilk. It plays a positive role in digestion and has immunological effects for your baby, including protecting their body against infection from intestinal parasites and releasing free fatty acids that provide antibacterial and antiviral effects. When Lipase is unusually high, it works overtime to break down the fats, resulting in an aroma or taste that your baby might find unpleasant. The rate at which this change occurs is different for each mom. It can happen in a matter of hours or over the course of several days.


    The first thing you should know is High Lipase is not harmful to your baby at all. Still, sour-smelling milk can be devastating. There are a few ways to eliminate the soapy/metallic taste and smell, and your Ceres Chill Breastmilk Chiller can help!


    Before Ceres Chill, scalding High Lipase milk was a hassle. The stovetop method was the only way to prevent the change in taste or smell, so there was virtually no way to do it when you were out and about. The steps were tiresome and the dishes piling up at the end of the whole ordeal just added to the burden.


    Scalding can be quick and easy if you have the right tools. A bottle warmer and your Chiller are all you need. After filling the inner chamber of your Chiller with breastmilk, warm it up to 180° F and use a thermometer to ensure that it’s at the right temperature. Be sure to place ice and water into your Chiller's outer chamber in advance so that when your milk is done heating up, you can pop it right in for an ice bath!

    Heating Milk Instructions


    If you need to scald your milk at work or on the go, Ceres Chill can make it happen. For this method, you’ll need two Chillers - one to scald and one for the ice bath. Before leaving to start your day, fill one of your outer chambers with 180° F water. Fill the other Chiller with ice and water.

    After pumping into your inner chamber, screw it into the outer chamber with the hot water and seal everything tightly. Use a thermometer to keep track of the temperature of your milk. Once it reaches 180° F, take the inner chamber out and immediately plunge it into the other Chiller for an ice bath. You can continue to pump and scald throughout the day while storing all of your milk in the Chiller that holds the ice and water.

    Check out this awesome video for a tutorial on using your Chiller to scald milk!


    Since the flavor of High Lipase milk can change over the course of hours or days, it's important to check your stash. The last thing any mom wants is to feel like all of their liquid gold has gone bad. If this does happen to you, you still have options! Try mixing it with freshly pumped milk, adding a drop of non-alcoholic vanilla, combining it with solid food or using it to make some good ol’ therapeutic breastmilk soap.

  • Formula 101 – Everything you need to know!

    By Jael Corr

    Ceres Chill is so pleased to bring you Jael's comprehensive guide to formulas —
    she is a writer and proud mom of six amazing kids between six months and sixteen years old.

    Like many new parents, I started off wanting to exclusively breastfeed. That was my goal! I really wanted to make it work for me and my family, but after trying for weeks, I realized that it just wasn’t the best fit for me. I started looking into formula feeding and realized that supplementing could be really beneficial for both me and my baby. It allowed me to get some much-needed rest and care for myself while also ensuring that my baby was getting all the nutrients they needed!

    Navigating the world of formula felt really overwhelming at first. There are so many options out there, and it can be challenging to determine which one is best for your baby’s specific needs! After researching and consulting with my pediatrician, I learned about all of the different ways that I can make it work for me. Everyone’s feeding journey is unique, and while some parents exclusively breastfeed or formula feed, many parents choose to supplement their baby's nutrition with a mixture of breastmilk and formula. 

    Finding the feeding option that is most beneficial for you and your baby can feel daunting at first, but I'm here to help! Just remember that at the end of the day, a fed baby is a healthy baby, no matter how you’ve chosen to accomplish that. You are doing an amazing job either way. 

    There are various types of baby formulas available, each designed to meet the unique nutritional needs of babies with different health conditions and dietary requirements. Check out the list below to read more about the various types of baby formulas.

    Quick reminder — It's important to consult with a pediatrician before choosing a formula to ensure that it is appropriate for your baby's specific needs. For medically compromised babies, please be sure to reference the World Health Organization's guidelines for formula preparation. Always use clean water when preparing formula.


    I know, it seems like a lot … but don’t worry, I tried to break it down so you can easily access all the info you may need. 

    • Hybrid (combining breastmilk with formula)
    • Ready-to-feed (pre-mixed and ready to use without the need for mixing or preparation)
    • Powdered milk-based (made by mixing powdered formula with water)
    • Goat milk (made with goat milk instead of cow's milk and a good option for babies who are sensitive to cow's milk)
    • Lactose-free (designed for babies who are lactose intolerant)
    • Allergen-free (designed for babies who have food allergies or sensitivities to specific ingredients such as soy or dairy)
    • Genetically engineered (made with ingredients that have been genetically modified to enhance their nutritional content)
    • Soy-based (made with soy protein instead of cow's milk protein and a good option for babies who are allergic to cow's milk)

    • Hydrolyzed  (made with proteins that have been broken down into smaller fragments, making them easier to digest for babies with digestive issues)
    • Organic (made with organic ingredients and are free from synthetic pesticides and fertilizers)
    • Hypoallergenic (designed for babies who have allergies or sensitivities to certain ingredients and are less likely to cause allergic reactions
    • Anti-reflux (designed to reduce the incidence of spit-up and reflux in babies)
    • Premature (designed for premature babies, providing extra calories and nutrients to support their growth and development)
    • Metabolic (designed for babies who have metabolic disorders that affect their ability to metabolize certain nutrients


    The Chiller can be great for convenient and safe storage of formula while you’re out and about!

    There are a few different ways that you can use it depending on what you need.

    1. Add boiled water to your outer chamber, cap it up, and leave it in your bag until you’re ready to make a bottle! Without ice in one of the chambers, the Chiller will sustain the temperature of the warm water and keep it at a good temperature until you’re ready to make a bottle. Measure out the amount of warm water that you need, either in your own bottle, your inner chamber (12 ounces) or your upper cup (just over three ounces). Then add your powder formula, mix it up, and feed your baby.
    2. Have ready-to-feed formula in one chamber, and ice in the other. This method is really similar to the way that you would use the Chiller to store breastmilk or other liquids. By adding ice to one chamber and adding your formula to the other, the Chiller will work to keep it at safe, cold temperatures for several hours. 
    3. Have your powder formula in one chamber and clean water in the other. When you’re ready to prepare a bottle, mix the correct amount of powder and water together, and shake it up as usual!
    4. It’s generally recommended to make your bottles of formula right before giving them to your baby, but ... if you need to premix your powder formula before heading out for the day, you can do so and store it in one of the Chiller chambers. It’s essential to have ice in the other chamber and to refill it every few hours to ensure that the formula is staying within the safe storage range. This formula will stay good for 24 hours if it’s kept below 39 F.

     You can also convert your inner chamber or upper cup and connector to a bottle by adding any standard narrow neck nipple. Check out this awesome tutorial to see how to store formula in your Chiller!

    As a parent, I understand the importance of choosing the best formula for your baby and making sure it's stored safely. It's crucial to follow the right guidelines to ensure that our babies are getting the best nutrition and staying healthy. Before storing your formula in the Chiller, be sure to check the back of your formula can for all information regarding length of storage time and other details!


    Formula recalls will often be on the news and on social media, and the manufacturer has an obligation to communicate these issues with customers.

    To find out if the formula you're using has been recalled, you can search the seven-to-nine digit lot code on the bottom of your can and see if it is part of the batch that was possibly contaminated. The U.S. FDA always tracks all formula recalls. Check out this information that they've put together.


  • Formula + breastmilk = combo feeding

    By Jael Corr

    Like many new parents, I started off wanting to exclusively breastfeed. That was my goal! I really wanted to make it work for me and my family, but after trying for weeks, I realized that it just wasn’t the best fit for me. I started looking into formula feeding and realized that supplementing could be really beneficial for both me and my baby. It allowed me to get some much-needed rest and care for myself while also ensuring that my baby was getting all the nutrients they needed!

    Navigating the world of formula felt really overwhelming at first. There are so many options out there, and it can be challenging to determine which one is best for your baby’s specific needs! After researching and consulting with my pediatrician, I learned about all of the different ways that I can make it work for me. Everyone’s feeding journey is unique, and while some parents exclusively breastfeed or formula feed, many parents choose to supplement their baby's nutrition with a mixture of breastmilk and formula.

    Per the USDA, combo feeding refers to formula + breastmilk, and it comes in many forms. It can mean alternating between breastfeeding and bottle feeding with formula, pumping and bottle feeding, creating a mixture of formula and breastmilk, and more. There are many ways to combo feed! 

    When you’re combo feeding and you don’t have enough breastmilk to fill an entire bottle, you have some options: wait for the next pump session to add more milk, make a mixture of formula and breastmilk, or offer the bottle of breastmilk first and then offer the formula after if your baby is still hungry.

    If you’ll be mixing your milk and formula in the same bottle, it's important to keep in mind the proper ratio and handling of the mixture when preparing it - the standard ratio for mixing formula with breastmilk is 1:1. If you have frozen breastmilk, you can still mix it with formula if the mix is first thawed out. Ideally, you should thaw it by placing it in the refrigerator or holding it under warm running water.

    Sometimes, though, mixing breastmilk and formula in the same bottle can result in wasted milk. 

    According to board certified pediatrician Maya Muñoz Mahmood, “There aren’t any health risks involved in mixing breast milk and formula, but doing so could result in wasted breast milk. If a baby does not finish the bottle they already started, the remainder needs to be thrown out within an hour, which is the rule for prepared formula or breast milk mixed with formula,” Mahmood says. “So, any remaining breast milk that was mixed in would be ‘wasted.’ For many parents who are pumping, every ounce of breast milk feels precious. So, they’d rather not risk having to toss any leftover breast milk.” — Can you mix breastmilk & formula? Experts explain ( 

    To ensure that this doesn’t happen, she recommends giving your baby the bottle of breastmilk first, then following it up with the bottle of formula if they’re still hungry. 

    Finding the feeding option that is most beneficial for you and your baby can feel daunting at first. Just remember that at the end of the day, a fed baby is a healthy baby, no matter how you’ve chosen to accomplish that. You're doing an amazing job either way.

  • Milk donation 101: Formal and informal sharing

    If you can’t breastfeed, you can still give your baby the benefits of human milk 

    There are several reasons why a parent might need donor milk, and chief among them is difficulty producing enough milk. And there are a dozen reasons that contribute to a low supply, including babies who are born prematurely with special medical needs. The World Health Organization and other experts agree that donor milk is the next best option for parents who aren’t able to produce the amount of milk that their babies need, especially for medically fragile children. Thankfully, there are ways to help make sure that they receive the benefits of breastmilk through milk donated by other moms!

    According to Kelly and Celia, founders of breastmilk sharing app Share the Drop, “Some groups that benefit from donor milk include:

    • Any female unable to produce enough milk  
    • Breast cancer survivors 
    • Adoptive and foster parents 
    • Gay couples that adopt infants 
    • Families that use surrogates without access to breastmilk 
    • Non-parental guardians caring for an infant 

    While breastfeeding is supposed to be the most natural thing our bodies do (it’s why we have mammary glands), the process itself can be fraught with complications for some women. When it becomes difficult, the anxiety and stress over feeding can be isolating and depressing. Some women return to work and struggle to keep up their supply. Others may be forced between taking life-saving medication and continuing to breastfeed.”


    It’s not uncommon to produce more milk than your baby drinks or needs. In cases of oversupply or extra milk stored in the freezer, many parents make the choice to donate it to other families. Mothers who experience the loss of a child might also choose to donate their milk to help premature or otherwise sick children. Milk donation is unpaid - it is simply a gift that is given to babies who need it.


    When donating through a formal milk bank, there is a system in place to ensure that the breastmilk that is being donated is safe for use for babies with medical needs. When you arrive to sign up as a donor, you will be required to make a record of your medical and lifestyle history. You will need to provide a letter from your physician confirming that you are in good health, and you will need to bring blood tests to detect HIV, HTLV, hepatitis B & C or syphilis. You will also need to let the milk bank know what medications you’re currently taking and keep them updated on any changes in the future as you continue to donate. The full qualifying process can take a few weeks. 

    Sending in your milk

    According to Helping Hands Milk Bank, you can donate recently expressed milk or previously collected milk that has been frozen up to 10 months from the date of expression. The date of expression (month, day and year) must be clearly marked on the bags. Once you are approved as a donor, you can either visit your local milk bank to drop off your milk, or you can request supplies to ship your milk. Many milk banks will provide you with a cooler and ice packs.

    Final steps

    Once the milk bank receives your donation, the milk is laboratory processed, pasteurized (which eliminates bacteria while maintaining the majority of the beneficial components of the milk), tested for microbiological cultures, then sent to recipients. 

    “These multiple overlapping screening and safety steps ensure that pasteurized donor human milk is safe for the most vulnerable infants. In over 40 years of modern milk banking there has never been a documented case of an infant being harmed by donor milk.” — Mothers’ Milk Bank Northeast 


    • A positive HIV, HTLV, hepatitis B & C or syphilis blood test.
    • A donor or partner who is at risk for HIV.
    • A donor who uses tobacco products, illegal drugs, cannabis, or daily use of alcohol. There is a waiting period that is required after you drink any alcohol. 
    • A donor or sexual partner that has received a blood transfusion in the 4 months prior to milk collection.
    • A donor or sexual partner that has received an organ or tissue transplant in the last 12 months.

    Some milk banks might have other disqualifying rules, so be sure to call or check your milk bank’s website before going to get screened. 


    • Pasteurized (heat-treated) to eliminate bacteria or viruses that may have been present in the milk. Although some nutrients are lost in pasteurization, donor milk is still better for your baby than infant formula.
    • More easily digested by babies, which could mean fewer days of intravenous nutrition.
    • Possesses incomparable immunological properties that can help protect against a wide range of illnesses and serious infections.
    • Contains specific elements that protect the intestines against harmful bacteria and viruses. 


    We know breastmilk promotes gastrointestinal and immune function and contributes to disease prevention throughout a child’s lifetime. Breastfed babies generally experience fewer colds and respiratory illnesses, fewer ear infections and even better vision. The benefits span their lifetime, with fewer instances of allergies, eczema, heart disease, and more. What’s less known and discussed in medical settings and social circles are the health benefits that breastfeeding provides the mom. Here are a few:

    • For every 12 months of cumulative breastfeeding, the risk of breast cancer is reduced by 4.3%
    • Breastfeeding for 6 months or less reduces the risk of ovarian cancer by 17% and breastfeeding 6 to 12 months reduces the risk by 28%
    • 12 months of breastfeeding is associated with a 9% reduction in the development of Type 2 diabetes
    • Breastfeeding for at least 12 cumulative months reduces the incidence of hypertension, diabetes, and hyperlipidemia, all contributing factors to cardiovascular disease
    • Women who breastfeed are less likely to experience osteoporosis 


    Go through a milk bank

    A human milk bank is a service that collects, screens and distributes human milk. The milk is donated by nursing mothers who are not biologically related to the infants receiving it. 

    Find a milk bank to donate or receive donor milk:

    International Milk Banking - World Bank Map

    Mothers Milk Bank

    Tiny Treasures Milk Bank

    UC Health Milk Bank

    Milk Banks Near You

    Use an informal milk-sharing network

    Milk sharing is the process in which families share breastmilk with other families without going through a milk bank. There are several organizations that help facilitate milk sharing in communities. Share the DropEats on FeetsHuman Milk 4 Human Babies, and MilkShare are just a few!

    “The benefits of breast milk have long been touted by organizations like the American Academy of Pediatrics, Centers for Disease Control, and World Health Organization. Nutrients in breast milk are better absorbed than the sugar and protein found in formula and it contains disease-fighting factors that can prevent infections. Our app and web platform allow you to create a profile in seconds, and instantly start finding donors in your area based on geolocation – like a dating app. You can filter through possible matches by age of their baby, amount available, and dietary intake such as dairy-free, caffeine-free etc.”

     — Kelly and Celia from Share the Drop

    If you choose to go the informal route to donate, be sure to read the information offered by the organization and ask as many questions as you need to ensure that you feel comfortable and that you’re providing milk in a safe and protected way. Many of these organizations will often have an agreement that needs to be signed by both the donor and recipient to protect both parties.

    Check out Kelly and Celia’s recommendations: 

    • Have open, honest conversations with your potential donors so you can understand their lifestyles
    • Discuss handling and storage techniques 
    • Share or request medical documents as you wish 
    • Utilize home pasteurization methods if you choose 
    • Use testing strips for protein or alcohol if you have a concern 
    • Meet up with your match in a public place and bring your cooler full of ice packs 

    “We believe that access to breast milk and inclusivity is important, and our app provides just that for babies and parents in need seeking the option.” — Kelly and Celia from Share the Drop


  • The science of pooling milk

    Let’s get nerdy with friend and inspiration Dr. Trill! She covers the science and citations to help explain all the principles for pooling milk safely, and we're so grateful. Read on!

    By Trillitye Paullin, Ph.D.

    Women are often advised not to combine milk from different pumping sessions, citing reasons such as increased bacterial contamination and temperature differences. Let us dig deeper into this myth and discuss what it could mean for parents, including those of babies with higher risks such as preterm birth or food allergies.

    I am a mother to two beautiful daughters born with severe infant food sensitivities who discovered that many parents experience the same troubling situation. I created Free to Feed to be a place for parents to find answers to their questions about infant food sensitivities and empower them to continue their breastfeeding journey.


    Over the course of 4 different days, scientists collected milk from 19 mothers. Day 1: 24-hour pooled breastmilk and Day 2: 24-hour breastmilk separated by pump session (non-pooled). The following week, mothers repeated the collection on alternate days (day 1 separate, day 2 pooled). Bacteria analysis through plating found colony counts ranging from 0 to >100,000 per milliliter (mL). Counts over 100,000/mL were observed in 31 of 211 (14.7%) non-pooled samples and 3 of 35 (8.6%) pooled samples. This means that there was more bacteria found in the non-pooled samples than the pooled samples, however the difference was not statistically significant [1]. ​These findings demonstrate pooling breastmilk does not increase bacterial contamination. These results can be explained by a separate study which found the largest contributing factor to expressed breastmilk bacterial contamination is collection and storage material cleanliness [2]. 


    Breastmilk nutrition content varies throughout the day. Some parents may attempt to match when the milk was expressed to when baby receives that milk (morning pump sessions fed to baby another morning). This is not always feasible. Instead, pooling a days’ worth of pump sessions creates more consistent macronutrients. In the same study as above, scientists found a macronutrient variability range of ±32% for protein, ±46% for fat, ±30% for carbohydrates, and ±29% for total calories [1]. This is especially vital for preterm and NICU infants who may be receiving expressed and fortified breastmilk as consistent nutrition can improve health outcomes [3]. 


    The advice to not combine freshly pumped milk to chilled refrigerated milk is based on the assumption that it will significantly impact bacterial contamination and/or nutritional content due to the temperature changes. As discussed above, temperature fluctuations in pooled milk do not lead to increased bacteria counts or nutritional breakdown. In fact, the study found that the average nutritional content of 24 hours worth of individually stored milk was nearly identical to that of the pooled samples and that pooled milk did not have increased bacterial contamination [1]. 


    Mothers who tried both pooling and non-pooling methods reported pooling to be easier overall, citing items such as less plastic usage and easier storage [1]. From personal experience, I can say that pooling has been an absolute necessity while I have been on military duty, traveling, or simply forgot to bring extra containers to work. It is essential for mothers in this situation to not feel as though they are somehow giving “subpar” milk to their infants. If anything, it should be encouraged to make mom’s life easier and babies healthier. 


    General rule of thumb should be dependent on your baby’s reactions. If ingested foods in your diet cause food allergy symptoms in baby, you should be aware of how pooling could impact your milk. We know that allergen protein concentrations typically spike around 2 hours post-ingestion and steadily decrease after that [4-7]. Pooling milk will reduce the overall allergen protein concentration if you do not continue to consume it throughout the day. This may be an option if you know what your child is allergic or sensitive to and symptoms are not life-threatening. Essentially, if you would feel comfortable giving all of the expressed milk to your little one separately, then pool-on momma! However, if you do not yet know what is causing reactions, pooling can add another layer of mystery to your already difficult situation. This is because you will not know which pumping session contained the allergen in order to investigate your diet thoroughly. As with all things food allergy-related, consult your physician for further assistance. 


    Feel confident pooling your pump sessions! Having a single container to hold expressed milk can help decide how to best portion out what will be used immediately and what needs to be frozen. Reduce dishes and how much plastic-wear you need to lug around on your daily commute or traveling. Understand that when labeling milk and determining how long it is good, you should use the oldest expression date/time for all of the pooled milk.


    1. Stellwagen, Lisa M., et al. "Pooling expressed breastmilk to provide a consistent feeding composition for premature infants." Breastfeeding Medicine 8.2 (2013): 205-209. 
    2. Haiden, N., et al. "Comparison of bacterial counts in expressed breast milk following standard or strict infection control regimens in neonatal intensive care units: compliance of mothers does matter." Journal of Hospital Infection 92.3 (2016): 226-228.
    3. Heiman, Howard, and Richard J. Schanler. "Enteral nutrition for premature infants: the role of human milk." Seminars in Fetal and Neonatal Medicine. Vol. 12. No. 1. WB Saunders, 2007. Vadas, Peter, et al. 
    4. "Detection of peanut allergens in breast milk of lactating women." Jama 285.13 (2001): 1746-1748. Palmer, D. J., M. S. Gold, and M. Makrides. 
    5. "Effect of maternal egg consumption on breast milk ovalbumin concentration." Clinical & Experimental Allergy 38.7 (2008): 1186-1191. Zhu, Jing, et al. 
    6. "Discovery and quantification of nonhuman proteins in human milk." Journal of proteome research 18.1 (2018): 225-238. 7. Picariello, Gianluca, et al. 
    7. "Excretion of dietary cow’s milk derived peptides into breast milk." Frontiers in Nutrition 6 (2019): 25.

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