Your baby can afford to lose up to ten percent of his or her birth weight in the first week after his birth, if he is not born prematurely.

Although the research tells us that a weight loss of up to 15% may occur in some babies without the baby's safety or health being threatened (as long as you are offering breastfeeds frequently and flexibly), your baby will need to be under the care of your health professional after 10% of birth weight is lost. This is to ensure your baby's safety, as your milk production increases and your baby turns around her weight gain.

The very large World Health Organisation research study which was used to create the WHO growth charts showed that successfully breastfeeding babies gain about 200 gm to 250 gm a week in the first couple of months of life. (Little boys tended towards the 250 gm/week, little girls towards the 200 gm/week.)

Health professionals like to see babies regain their birth weight by about two weeks after the birth. However, some babies return to birth weight a little later than that. However, these little ones who are slow to regain their birth weight but otherwise safe and well-hydrated require very close monitoring by your GP or other health professional.

Many babies track on a percentile line that is one line lower than the percentile line of their birth. Some health professionals prefer to weigh babies when they are 24 hours old for their birth weights, to give baby time to wee out any extra fluid that might have come into the baby from your own intravenous fluids during the birth process.