Point-of-Care : Maternal & Women's Health : Breast milk and Creamatocrit Plus


Measuring creamatocrit and increasing fat in breast milk

What is creamatocrit?

The creamatocrit is a quick, accurate and easy-to-perform measurement of the lipid content in mother’s milk. Used extensively in lactation research since 1978, it involves placing a few drops of milk in a capillary tube, and centrifuging it so that the lipid – or “cream” – separates from the aqueous part of the milk. The percent of cream to total milk volume is calculated and converted to estimate of lipid and caloric content.


Previously, the creamatocrit test was performed with a cumbersome laboratory centrifuge and calipers, which limited its clinical use.

Why is it useful to measure the lipid and calories in breast milk?

Mothers feel great when they see their breast milk’s nutritional value. This especially holds true for the mothers of premature infants, who are able to go back to the NICU and speak to the doctor with confidence regarding the caloric supplementation of their breast milk. They often get approval for vitamin and mineral supplementation only, not supplementation for calories.

How is creamatocrit used?

  1. As a scientifically supported motivation for breastfeeding compared to infant formula.
  2. As a teaching tool when the baby is not achieving desired weight gain.


How to increase fat in breast milk?

The milk production and amount of fat content of milk can vary during a pumping session and at different times of the day. If the baby doesn’t get enough fat, he or she may have trouble gaining weight.

Fat in mothers’ milk can be increased to help babies grow.


Foremilk and hindmilk

The first milk that comes out of the breast during a pumping or feeding session is called “foremilk.” Foremilk is mostly water. It contains protein and other nutrients, but it is low in calories and fat.


As the breast is emptied, the amount of fat in the milk gets higher and the milk has more calories. The milk at the very end of a pumping or breastfeeding session is called “hindmilk."


The milk can be separated to collect milk that is higher in fat and calories. If a mother makes lots of milk (more than 900 ml per day), or if she gets a lot at one pumping (more than 200 ml), the milk might be watery. It may need to be separated to increase the fat.


It is helpful to know how much milk is obtained from each breast at each pumping session. The mother can be instructed to remove the first one-third that is pumped. For example, if the mother normally pumps 60 ml on each breast, the first 20 ml (foremilk) can be removed and frozen for later use. The remaining 40 ml can be fed to the baby.


Testing the fat

A creamatocrit analyzer can be used to measure the amount of fat and calories in the breast milk, letting the baby’s care team know exactly how many calories the baby is getting. Generally, human milk contains about 20 calories per ounce, but the fat content can vary greatly throughout the day and during a single pumping session. To better understand the fat and calories of a mother’s breast milk, mothers can save milk that has been pumped at different times of the day so it can be tested.


Fractionation of human milk

Because the fat content of human milk varies from mother to mother and during individual pumping sessions, a creamatocrit centrifuge is used to evaluate the fat and calorie content of the milk. Mothers can be assisted in separating their milk to provide the best nutrition to their infant.



Directions for separating milk:

  1. Have extra breast milk storage containers ready.
  2. Begin pumping breasts with the breast pump. About two minutes after the milk starts flowing steadily, turn the pump off, pour this milk into a separate container and label it “foremilk.” This should equal about one-third of the usual amount the mother pumps.
  3. Continue pumping until the milk flow stops, then for two more minutes. Label these bottles “hindmilk.”
  4. The mother’s milk may need to be separated a few times before the baby's care team determines which is the best milk to feed to the baby.
  5. Hindmilk can be fed to the baby to help with growth and development.


Skim milk

Some infants — such as those with chylothorax — may require fat free milk. The breast milk can be spun in a cold centrifuge to create skim milk. The milk can be tested on the creamatocrit centrifuge to ensure it is under a certain number of calories. This allows the infant to get the immuno-biological and nutritional benefits of human milk.


How often should a mother be tested?

The frequency with which a mother should be tested depends on the situation. If the device is used to support breastfeeding by showing the mother just how good her milk is, then perhaps one test is sufficient.

However, in a Neonatal intensive care unit (ICU) the mother’s milk may be tested a number of times throughout a 24 hour period.

Breast milk and the Creamatocrit Plus™

Breast milk is the recommended form of nutrition for all infants for the first six months of life based on the American Academy of Pediatrics guidelines. This is due to breast milk’s unique nutritional composition and protective qualities which are proven to help safeguard against enteral feed intolerance, nosocomial infection, and necrotizing enterocolitis, as well as provide other immunological benefits.1 These benefits are even more important when applied to a pre-term or low birthweight (LBW) baby due to their vulnerable condition.


Several older studies indicate however that weight gain may be slower in human milk-fed than formula-fed premature infants, raising questions about the caloric adequacy of breast milk.2 This has led to a practice of using formula and fortifiers in many NICUs across the country as an exclusive form of nutrition for premature, LBW infants.


Lipid concentration in breast milk varies considerably, depending upon the stage of lactation, frequency of milk expression, time of day, and completeness of breast emptying. The lipid concentration contributes the majority of the calories in breast milk, so fluctuations always affect caloric density.


The point of care Creamatocrit Plus™ provides objective and real-time information about the caloric content of any given breast milk sample.3 This provides nutritional data for neonatologists, registered nurses, lactation consultants, and nutritionists to individualize feeding interventions for infants in a variety of ways and in a variety of settings. In the NICU, the Creamatocrit Plus is instrumental when performing hindmilk fractionation of breast milk which has shown to accelerate weight gain in LBW infants without the use of formula or fortifiers.


This analyzer is also a valuable diagnostic tool for Lactation Consultants to manage breastfeeding problems with mom. The test results can be used to confirm lipid concentration variations and help LC’s to prescribe a corrective milk expression schedule or changes to storage techniques.2 Mothers also feel assured when they see that their breast milk has enough calories, especially in comparison to infant formula, thus encouraging them to continue with their breastfeeding efforts. Mothers can be taught to separate the foremilk from the hindmilk at the time of pumping and feed the high calorie hindmilk in cases where babies are not achieving desired weight gain.


The Creamatocrit Plus is an essential tool to validate the caloric benefits of breast milk allowing clinicians to utilize breast milk confidently as the nutrition of choice, helping ensure that the youngest lives get the healthiest possible start.


Creamatocrit Plus-Mothers-Milk-Analyzer


  1. Breastfeeding and the Use of Human Milk. American Academy of Pediatrics. Pediatrics, Feb 2005;115(2):496-506.
  2. Creamatocrit Measures with Mothers’ Milk: Utility in Neonatal Intensive Care. Rush Mothers’ Milk Club Special Care Nursery, 2006.
  3. Accuracy of a User-Friendly Centrifuge for Measuring Creamatocrits on Mothers’ Milk in the Clinical Setting. Meier, Paula et. al., Breastfeeding Medicine, Jun 2006; 1(2): 79-87.

“Creamatocrit helps us explain to mothers and providers how much more nutritious breast milk is. This helps parents and providers choose breast milk over formula when there is a need for supplementation. It is very easy to use and very reliable. The need to know calorie content, especially for premature and high risk babies is why we decided to start using is and it’s been the best decision”.

Susan Glaeser
RNC, BSN, IBCLC RN-Supervisor,
Mom’s Place WIC Austin, TX