Tell this doctor that your *anthropologist* friend who does research on
breastfeeding in Mali (West Africa) would REALLY REALLY REALLY REALLY like
to have his reference for this 90% figure.  Ask him nicely and sincerely,
for me, please. :)

 It is true that there are some cultures where the infant is wet-nursed, and
some where it just isn't fed at all til the milk "comes in" and still others
where it gets a "medicinal" tea, but these examples are by no means the vast
majority (as 90% would be).  In most places, baby goes to breast within the
first 23-48 hours, and no one is around to check bilirubin levels or
dehydration, but most babies do fine.  You might also provide him with some
references on the "normality" of high bili levels.  Human babies are
designed to expect that only their mother will nurse them (no ABM, no wet
nurses).