Diane, you may be right that the physician wants only "to make the
diagnosis of breastmilk jaundice".  But any physician worth his salt,
and I admit there are many out there who are not, can make this
diagnosis *without* stopping breastfeeding.  After all, you have a
thriving, healthy baby, whose liver and spleen are not enlarged, who
nurses beautifully (on observation).  You should check the urine
(office procedure) to rule out a urinary tract infection, and the fact
that the urine has no bilirubin in it (dipstick--a test, not a
description of the physician).  You can check the hemoglobin and
retics, to make sure there is no hemolysis (though in a 3 week old
this hardly seems necessary), and, if you want, check the TSH to make
sure the thyroid screen did not screw up (quite rare problem, uncommon
for the lab to screw up).  This is the *most* which need be done, and
the whole thing would not take more than 15 minutes.

There is no need to stop breastfeeding for jaundice (except for
galactosemia, which causes the baby usually to be extremely ill and
have brown urine).  If the breastfeeding is going well, rule out a few
problems, as above, and do not worry about the jaundice.  And if the
breastfeeding is *not* going well, do not worry about the jaundice and
fix the breastfeeding. Do *not* sacrifice breastfeeding on the altar
of ignorance.  I really hate this "we'll stop for a couple of days
*just to make sure*".  The message is that the jaundice is more
dangerous than the artificial baby milk.  And as a result, many
mothers stop altogether.

Jack Newman, MD, FRCPC