According to a seminar I attended on ultrasound views - if the milk is not pulled from the breast, it retreats back into the alveoli and ducts further back in the breast that are less full (where the pressure is lower).  Thus, the next ejection, there is less force behind the contractions (theoretically) resulting in less volume being expelled in succeeding ejections.  This is PROBABLY why double pumping results in better volumes and the more efficient the pump is and better fitting, the better the overall results are.  And why pumps can cause oversupply in women gifted with higher potentials, etc.  So - if I have a mom that has historically dealt with oversupply and MUST pump, I might encourage her to only single pump, as if she had one nursing baby instead of two.  Don't know if that would be considered an acceptable care plan - but have found that worked.  

-----Original Message-----
From: Lactation Information and Discussion [mailto:[log in to unmask]] On Behalf Of Christina
Sent: Monday, November 01, 2010 1:35 PM
Subject: curious question about milk movement in the breast

That's a question I got today from one of the peer counsellors-to-be I am working with:

Since we know that milk ducts do not store the milk, what happens with milk after a milk ejection, if the baby does not want to nurse on the second breast for instance? Does it travel backwards to the alveoli or what?

I know I have seen it mentioned a number of times on the list that there is a bolus of colostrum immediately after the birth which is available if the baby has the opportunity to suck or if it is expressed immediately. And that's not the case some hours later, if you try to express, so there is the possibility that the milk or colostrum goes back deep into the breast somehow. But I wonder if there is a scientific explanation of this process somewhere?

Christina Yaneva
BF Peer Counsellor
Bulgaria

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