Have been involved in a discussion elsewhere, and need to know what you all think.  

I know that meconium is made up of the solid matter filtered out of the amnionic fluid during the course of gestation.  The baby swallows and filters, pees off the liquid, and shunts the dead skin, lanugo, vernix, hair, to the bowel.  And (I think) I know that even in utero, there is some processing of bilirubin, with secretion into the bowel.

My question concerns the jaundice that babies develop after birth.  Is this a reaction to the bilirubin accumulated into the meconium during gestation?  Or is it a consequence of additional bili being created -- due to the various factors of birth and neonatal life -- that is not yet being excreted because the baby still hasn't started to poop out the old, much less process the new?

My understanding is that we have moms (of jaundiced babies especially) breastfeed, breastfeed, breastfeed, so babies will poop, poop, poop, so the new breakdown products will get excreted into the bowel instead of recirculating in the blood and getting more and more concentrated, causing rising bili levels.

I've stated this as clearly as I can, so I hope y'all can figure out what I'm saying and asking.  Have talked to a couple of pedis and pedi residents at work who admitted they don't really know, but their instinctive (might we say gut) reaction is to say that the jaundice stems from the as yet unprocessed by-products, not the stuff already processed by the liver and passed on to the intestines and bowel.

TIA for considering this question (and answering it)

Chanita, San Francisco