The study, published in the September issue of the Archives of Pediatrics & Adolescent Medicine, surveyed 1,295 hospitals in 21 Eastern states and the District of Columbia.

The researchers found that 1,215 (93.8 percent) of the hospitals distributed formula sample packs to at least some new mothers. Sample packs are often packaged as diaper bags that contain formula, coupons, advertisements, and baby products.

Among the organizations opposing the practice of distributing the sample packs are the U.S. Centers for Disease Control and Prevention, the American Academy of Pediatrics, the American College of Obstetricians and Gynecologists, and the World Health Organization.

The distribution of these packs differed by state and by region. In New Hampshire, for instance, 70.4 percent of hospitals distributed the packs, while 100 percent of those in New Jersey, Maryland, Mississippi, West Virginia and the District of Columbia did so.

There was some encouraging news. Out of the 80 hospitals that were free of sample packs, 20 had eliminated the practice before 2000 and 60 since 2000, indicating that this practice is changing significantly.

"Exclusive breast-feeding rates among young infants are discouraging low," the study's authors wrote, with only 11 percent of U.S. infants being exclusively breast-fed at six months.

According to the researchers, formula sample packs have been shown to undermine breast-feeding, making it important to eliminate them from hospitals. Fortunately, these findings suggest the practice of distributing formula sample packs may be on the decline.

More information

The National Institute of Child Health and Human Development has more about breast-feeding.