Breastfeeding: Refrigerating or freezing breast milk for more than 48 hours reduces certain health benefits, according to a US study just released.
However, breastfeeding campaigners here said breast milk was still preferable to formula milk because of its superior nutritional qualities.
The study found that fresh breast milk had a higher antioxidant capacity than formula milk. Levels of antioxidants remained the same in formula milk, whether refrigerated or frozen. However, the longer breast milk was stored and the lower the temperature, the more the level of antioxidants fell.
Antioxidants mop up free radicals - chemicals that damage cells and DNA. They are particularly important for premature babies because they often suffer from infections, have blood transfusions and intravenous nutrition.
The research was led by Prof Thomas Hegyi of the Robert Wood Johnson Medical School in New Brunswick, New Jersey.
"To preserve the antioxidant activity of human milk, storage time should be limited to 48 hours," he said.
"Refrigeration is better than freezing and thawing milk," Prof Hegyi added in a report in the journal Archives of Disease in Childhood.
The breastfeeding group, La Leche League, said fresh breast milk was always preferable to frozen milk.
Ms Margaret McGuigan, public relations officer for La Leche League, said most breastfeeding babies were receiving fresh milk. However, in cases where women had to return to work, breast milk could be refrigerated or frozen. "Breast milk is still so much better than formula," she said.
Breastfeeding campaigners have been calling for longer maternity leave so that women can continue breastfeeding for as long as possible.
The World Health Organisation and the Department of Health recommend breastfeeding for at least six months.
The current maternity leave provisions give 18 weeks' leave with the option of a further eight weeks' unpaid leave.
Ms McGuigan said that while breastfeeding rates were increasing, Ireland still had the worst breastfeeding rate in Europe, and perhaps in the world. While 99 per cent of Norwegian mothers breastfed, the Irish rate was about 40 per cent, she said.
Additional reporting: Reuters
