Breastfeeding a baby in the first six months of life — even if the child also receives formula — reduces the risk of sudden infant death syndrome  by more than half, according to a new analysis of national and international data. And the SIDS benefit starts to show up at 2 months of age, the data indicate. In fact, the study by researchers from the University of Virginia School of Medicine found that even if the mother stops breastfeeding the baby after two months, the protective benefit continues. “There are a lot of reasons to breastfeed. There are a lot of advantages to both the baby and the mother, and this is another reason to encourage mothers to breastfeed,” said Fern R. Hauck, one of the study’s main researchers. The analysis, published this month in the journal Pediatrics, offers encouraging and useful information for mothers of newborns, said Hauck, a professor of family medicine. “One of the most interesting findings is that any breastfeeding – it didn’t have to be exclusive – is quite protective of SIDS,” Hauck said. “That’s really good news for mothers, because not all mothers can or do choose to exclusively breastfeed, and their babies will still get the benefit of breast milk.” Previous studies have suggested that breastfeeding is linked to decreased danger of SIDS, a leading cause of death for babies 1 year or younger. But this study is the first to identify a minimum amount of time babies should be breastfed to get the anti-SIDS benefits. For babies younger than 2 months, nursing did not appear to yield protection from SIDS — but as a practical matter, nursing must start right after birth or the mother’s milk dries up. The Virginia study’s data included nearly 2,300 SIDS cases and more than 6,800 other infants. It included research from Chicago, New Zealand, Germany, Ireland, Scotland, and England. The analysis found that babies breastfed either partially or exclusively for more than two months, and up to four months, had a 40 percent decrease in SIDS risk;  if they were breastfed up to six months, there was a 60 percent reduction in risk. The improvement was only slightly higher for infants breastfed more than six months. SIDS risk