Free Baby Formula for Newborns Limited at New York City Hospitals It is part of the modern maternity experience: the pink or blue knit caps, the identity bracelet, the impossibly tiny jumpers, and not least, the goody bag filled with infant formula. But that is about to change for many of the 125,000 babies born in New York City each year. The New York City health department began a campaign on Wednesday to encourage hospitals to stop handing out that free formula, as a way, officials said, of encouraging more mothers to breast-feed. Dr. Thomas Farley, the health commissioner, said that 23 of the 40 hospitals in New York City that deliver babies had signed up for the campaign so far. They will not hand out formula to new mothers as they are discharged unless the mothers ask for it or a doctor orders it. The 23 participating institutions include the city's 11 public hospitals, which adopted such a policy in 2007. Dr. Farley said that 90 percent of New York City mothers start off breast-feeding, but that by the time their babies are 2 months old, only 31 percent are still doing so exclusively. The gift packs of formula undermine breast-feeding, he said. "It's something which we feel that we can change, and we think that mothers want to breast-feed," Dr. Farley said. The American Academy of Pediatrics recommends breast-feeding exclusively for six months, and continuing it for up to a year, while introducing other food. Mardi Mountford, executive vice president of the International Formula Council, which represents manufacturers and marketers, said the city's focus "on discharge bags with a small sample of formula is misplaced." She said research showing that gift bags deterred mothers from breast-feeding was not conclusive. The city's Health and Hospitals Corporation, which runs public hospitals, said that after it stopped giving out free formula and began extensive counseling of new mothers on breast-feeding, 35 percent of mothers were exclusively breast-feeding at eight weeks, up from 29 percent before the change. Ms. Mountford said the industry council supported breast-feeding, but believed that a more effective way to promote it would be to provide more support in hospitals and workplaces for mothers who breast-feed. "Certainly, once women return to the workplace, it's very difficult," she said. Dr. Howard Minkoff, the chairman of obstetrics and gynecology at Maimonides Medical Center in Brooklyn, which delivers about 8,000 babies a year, said his hospital was participating despite a possible financial cost. The hospital gets free baby bottles from the formula companies, saving it hundreds of thousands of dollars a year. It will still need bottles for mothers who opt not to breast-feed. "It is an act of will to decide the public health and well-being of the next generation is more important than that money," he said. New York's push will include an advertising campaign in hospitals and in subways to promote the benefits of breast milk, which, according to the ads, include lowering the risk of pneumonia, ear infections and diarrhea for babies.