The fattest baby I've ever seen was completely breastfed. I don't remember
his weights, but he was huge.  He is now a slim, lovely pre-schooler. I've
seen a couple of really fat babies and they have all slimmed down as they
got older. Babies seem to gain on their schedule, not ours. Both my babies
were quite "porky"  (not 25# at 3 months, but they had thunder thighs, many
chins, etc.). One is now very slim (at 16), the older is chubby (at 13) but
starting to slim down. He's always going to be a big guy and the other will
be slight. They are totally different body types--one like me, one like my
husband.

The interesting thing about the mother with this very fat baby was that she
came to see me for a pump trial. We tried every manual pump in my office,
the electric pump, and hand expression. Couldn't get more than a few drops
out. I like to think my technique is better now (this was a few years ago),
but I doubt if it would have made a big difference. She just wasn't a "good
milker," yet this baby obviously had NO problem!

Leslie Ayre-Jaschke, BEd, IBCLC
Peace River Breastfeeding Clinic
Peace River Alberta, Canada