Parents could be feeding their babies with bottles that have faulty volume markings, putting their infants at risk of obesity or organ damage.
A survey of 35 baby bottles conducted by Consumer Affairs found 15 had inaccurate volume markings by more than five per cent.
Some of the bottles, which were usually low-cost and from discount stores, overestimated the fluid volume by up to 40 per cent.
The Ministry of Health said babies who were fed with the bottles could have been drinking infant formula which was too concentrated.
"Formula that is too concentrated will provide excess energy (calories) and other nutrients," said the ministry.
"This could lead to overweight or obese babies and toddlers. It could also harm organs such as the kidneys, when they are still immature."
The ministry advised caregivers to take their baby bottles to a pharmacy, which would have accurate measuring equipment.
"Most feeding bottles are imported and some of these meet a European regulatory standard (the EN14350 standard) that means the bottles are accurate," it said.
Bottles which adhered to the European standard were often more expensive than those from discount shops.
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