New child growth charts which reflect the slower weight gain associated with breastfeeding could be soon be adopted in England.
Formula-fed babies grow more quickly
Current UK growth charts are based on predominantly formula-fed babies, which tend to grow more quickly.
The new charts have been drawn up by the World Health Organization.
They have been backed in a report by the Scientific Advisory Committee on Nutrition and the Royal College of Paediatrics and Child Health.
It is hoped that adopting the new standards could stop breastfeeding mothers being worried about their babies apparently failing to put on weight fast enough.
The expert report recommends that the WHO charts are used for babies aged two weeks to 24 months.
Although the charts are based on breastfed babies, they are designed to assess and monitor the growth of all babies.
Most experts agree that breast milk is the best source of nutrition for babies and the Department of Health recommends exclusive breastfeeding up to the age of six months.
Different growth patterns
The WHO charts aim to show how breastfed babies "should grow" - rather than how most babies do grow.
They are based on a select group of 8,000 babies from six cities around the world, who were entirely breastfed for six months, with continued breastfeeding into their second year, and where none of the families smoked.
Babies who are breastfed gain weight at a slower rate than their formula-fed peers.
Current evidence suggests that such a pattern of growth could potentially reduce the risk of later obesity.
It is estimated that if the new charts are adopted in the UK a quarter of all babies will be redefined as heavier than the norm.
Public Health Minister Dawn Primarolo said the feasibility of adopting the new charts would be assessed in a pilot study.
"We are committed to promoting breastfeeding and these new standards will help alleviate mothers' concerns regarding the difference in growth patterns often observed between breastfed and formula-fed babies.
"Our next step is to consider the practical aspects of implementing them effectively.
"It's important that we field test the new standards and put in place appropriate training for users."
Professor Peter Aggett, chairman of the Standing Committee on Nutrition for the Royal College of Paediatrics and Child Health, said adopting the WHO guidance could help to promote breastfeeding.
In turn, that could reduce the risk of children becoming overweight and developing life-threatening disease in later life.
Currently, only about 20% of mothers in the UK breastfeed their babies, and many of these also give their babies some formula.
A spokesman for the Welsh Assembly Government said had worked closely with the Department of Health on its expert report, but no decision had yet been taken on how to proceed.