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 [log in to unmask]