My exclusively breastfed son was 9 pounds 1 oz at birth - 93% percentile. at two weeks appointment he was around 9lbs or or 70% percentile. now at around 4 weeks, he is around 50% percentile. is it normal for babies to drop in percentile this early?

There is an initial weight loss during the first week of life. Your son shy gain weight and grow in height. A 4weej visit is recommended. Discuss the amount of formula, and feeding on a schedule without skipping feeds is advised. Discuss feeding problems, vomiting, spit ups and elimination pattern. A weight re check in another two weeks, after this evaluation will indicate if testing required.

Babies lose weight and quite a lot of fluid in the first 48 hours of life. At 4 weeks, he has regained his birthweight; good documentation that breastfeeding is going well. Watch for continued weight gain and stabilization along a growth curve in the next six months.