In response to Querida's comments on Australian practices:
I had 2 babies both with ABO induced jaundice - one born in WA (that's
Western Australia, for our overseas lactnetters) and levels quite high - the
paediatrician played a wait and see game (no bili lights), with twice daily
testing we were in hospital for 10 days and certainly no mention ever of
formula. (He actually told me not to start any other fluids until 7 months
when baby could hold a cup amd I'd skip the bottle stage all together - that
was 16 years ago tomorrow!)
The second was born in Queensland and was under lights within 24 hours, I
had had a caesar and my milk was slow to come in (OK they shouldn't be
related, just mentioned it), again no mention at any stage of formula.  That
little tike (not so little really, he weighed 11lbs at birth) fed every two
hours for 6 weeks.  Stayed in my room with the lights, too. 13 yrs ago.
At the hospital I worked in until very recently we certainly didn't reach
for the formula without a very good reason and jaundice with a baby who was
feeding and pooing isn't a good reason.  The mums were encouraged to feed
frequently, that's all.  In fact the only time we ever used formula in
breastfed babies was when the jaundice appeared to be secondary to poor
feeding - not a common situation!
Denise
Brisbane, Australia