A new device analyzes breastmilk to see if you are producing enough; should you buy it?

152917DF-EF90-4232-9AF1-1852FFAFB860

MyMilk Labs launches Mylee, a small sensor that analyzes breast milk at home is the title of a recent piece on TechCrunch:

Parents often worry about if their babies are getting enough nutrition or if they are producing enough milk. MyMilk Labs wants to give nursing mothers more information with Mylee, a sensor that scans a few drops of breast milk to get information about its composition and connects to a mobile app…

The Mylee launched at Disrupt with a pre-order price of $249 (its regular retail price is $349). Based in Israel, MyMilk Labs was founded in 2014 by Ravid Schecter and Sharon Haramati, who met while working on PhDs in neuroimmunology and neurobiology, respectively, at the Weizmann Institute of Science…

Breast milk changes in the first days and weeks after birth, progressing from colostrum to mature milk. Mylee scans the electrochemical properties of milk and then correlates that to data points based on MyMilk Labs’ research to calculate where the sample is on the continuum, then tells mothers if their milk is “delayed” or “advanced,” relative to the time that has passed since they gave birth.

[pullquote align=”right” cite=”” link=”” color=”” class=”” size=””]It could work, but we need much more data to know if it does work.[/pullquote]

Does it work? Should anyone use it? The short answers: it could work; we need to see data about its sensitivity and specificity; and lactation professionals have philosophical objections to it.

It could work

I can’t find much technical information about the device, but the theory behind it is sound. Lactogenesis II is the process responsible for the progression of breast milk production from colostrum, through transitional milk to mature milk. There is a biomarker that can be used to track progress through the progression.

The Relation between Breast Milk Sodium to Potassium Ratio and Maternal Report of a Milk Supply Concern (2017) explains:

The ratio of breast milk sodium to potassium concentrations (breast milk Na:K) dramatically declines … as lactation progresses through colostral, transitional, and mature milk production stages; thus, decreasing breast milk Na:K is an objective biomarker of mammary gland progress toward copious mature milk production over the first week postpartum.

When they compared the breastmilk of women reporting low supply to that of women with adequate supply they found:

…[E]levated day 7 breast milk Na:K occurred in 42% of mothers with a day 7 milk supply concern, compared with 21% of mothers without a day 7 milk supply concern (unadjusted relative risk, 2.0; P = .008) (Table II). The unadjusted odds of elevated Na:K were 2.7 greater (95% CI, 1.3-5.9) with maternal report of milk supply concern (reference = no concern, P = .01) and further increased after adjustment for maternal ethnicity (3.4; 95% CI, 1.5-7.9; P = .003).

In other words, in contrast to lactivist beliefs, women who reported low supply did not “misperceive” the situation. Their breastmilk had an elevated ratio of sodium (Na) to potassium (K).

If concerns about milk supply among exclusively breastfeeding women were primarily owing to a lack of knowledge about the signs of abundant milk production, then the expected outcome would be no difference in breast milk Na:K as compared with exclusively breastfeeding women without milk supply concerns… Instead, the observed prevalence of elevated Na:K was 2-fold greater in the mothers with milk supply concerns (42% vs 21%)… This result challenges the belief that milk supply concern in the context of exclusive breastfeeding is primarily maternal misperception…

If the Mylee device analyzes the Na/K ratio and compares it to the expected ratio based on time since birth, the device could diagnose insufficient milk supply.

Does it actually work?

There’s no way to know without analyzing data from large numbers of women. Even if the device can successfully predict low milk supply, we’d need to determine its accuracy. What’s the false positive rate (indicating low supply even though supply is adequate)? What’s the false negative rate (indicating adequate supply even though supply is low)? Without that information — from a peer reviewed scientific paper — it is impossible to know if the Mylee device does what it claims.

If it works, should we use it?

Not surprisingly, lactation professionals appear to be reflexively opposed to its use. Its mere existence poses a serious challenge to the cherished lactivist beliefs that insufficient breastmilk is rare, that women who report it are “misperceiving” the size of their supply, and that “trusting” their bodies is the key to successful breastfeeding.

But if it turns out that the Mylee analyzer has a high rate of accuracy, they may quickly change their assessment. Why? Because it could be a huge revenue source for lactation consultants.

The device is slated to cost $349, well beyond the means of most women. Lactation consultants could purchase the device and charge a fee for testing a client. If they charged just $25 per analysis, they could earn back the cost of the device after only 14 tests; thereafter, the $25 per test would be pure profit.

Being able to do the analysis would almost certainly improve the popularity of the lactation consultant relative to her peers. Moreover, in the situation where the test indicated a normal Na/K ratio, lactation consultants could reassure patients with objective evidence that their supply was adequate and that they actually should trust their bodies. In contrast, if the test indicated a high Na/K ratio, women could be assured that low supply was biological, not lack of effort on their part. It is possible that such testing could help determine the efficacy in increasing supply of pumping regimens and galactologue supplements and medications.

Should anyone buy the device?

Even though the theory behind it is sound, I’d need to see much more scientific evidence of efficacy before I would recommend it for anyone. An accurate test could be very beneficial. An inaccurate test would be worse than useless.