A new study suggests that many women receive IV fluids during labour and some of the newborn’s initial weight loss may not be to do with lack of breastmilk, but due to the infant regulating its hydration.
The study recommends using the baby’s weight at 24 hours rather than at birth as the baseline weight. The study is Neoll-Weiss J et al (2011) An Observational Study of Associations Among Maternal Fluids During Parturition, Neonatal Output, and Breastfed Newborn Weight Loss.
International Breastfeeding Journal 6,9. (from Gleanings in Midwifery Matters 2011 Issue 131.