Elisa - regarding your baby with a negative weight gain, I would doubt that
you could have detectable changes in weight over the course of a feeding.
As long as the child is weighed in the same 'state' before and after
feeding:  ie. with diaper on so that if the baby eliminates that weight is
not lost, and the baby doesn't spit up/vomit, then the only reason I could
see for this weight loss is that the scale is not internally consistent.
You could easily test this by repeatedly weighing a 10 lb bag of potatoes or
flour.  This kind of variation is not uncommon in spring scales.  Scales
based on levers and weights usually do a little better.  Hope this helps.
        Giosi Di Meglio, MD
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