This is an old study, however I believe it was carefully done. 
"Hyperbilirubinemia in the Breastfed Newborn: A Controlled Trial of Four 
Interventions."  Pediatrics, Vol. 91, No.2, Feb 1993, pp. 470-473.  Authors: 
Jorge C. Martinez, MD; M.Jeffrey Maisels, MB, B.Ch; Lydia Otheguy, MD; 
Horacio Garcia, MD; Monica Savorani, MD; Beatriz Mogni, MD and Jorge C. 
Martinez, Jr.

My favorite sentence is in the abstract. "If the infant is significantly 
jaundiced and a decision is made to intervene, parents can be given a number 
of options and can make an   informed decision regarding which, if any, 
intervention they prefer."

the 4 options for babies with bili >17 were:
1. continue to breastfeed and observe (if bili went above >20, BF was then 
interrupted and phototherapy and formula begun.
2. discontinue BF and give formula
3. dc BF, give formula and phototherapy
4. continue BF and give phototherapy.

Group 3 & 4 had best results and group 3 had very best results.  The main 
difference was bili declined slower in groups 1 & 4.  Altho mothers in 
groups 2 & 3 resumed nursing there wasn't any follow up to see how long BF 
continued for any group. [which would be another nice study :-)]

Of course this was all prior to the "sentinal event" pronouncement, but I 
think it still is valid.  In thinking about our practice, we rarely have a 
baby reach 17 and we mostly watch, encourage frequent feeds and daily bilis. 
A bottle here and there doesn't spaz us.  I think  one of the problems is 
that parents always question volume when BF and jaundice says to them "not 
enough," no matter how much we tell them that some jaundice is normal. 
Questioning her supply or quality of milk is a world wide reason for 
premature weaning.

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