My LO is 3 weeks old and I EBF. He wasn't gaining weight so the pedi had us starting supplementing formula after each feeding. Pedi said the type didn't matter as long as it was milk based. We started this 2 days ago and the first few feedings were ok. Now, LO is vomitting the formula up as soon as we start to burp him. He's never done this after breast feeding. We are only letting him drink .05 ounces before burping. Has anyone else experienced this? Could it possibly be the formula were using? I usually end up breast feeding him some more because he's still acting hungry. I will call the pedi tomorrow but just wanted advice from others who may have had the same issue. Feeding is becomming over an hour long process and is exhausting! Plus, I'm trying to pump after each feeding to increase my supply!