Healthcare providers might be as equally confused about infant feeding guidelines as mothers, the authors wrote, saying some clinicians "may rely on their own infant feeding experience rather than evidence-based guidelines when counseling women."
The authors cited 40 percent of U.S. obstetricians from an earlier study who rated their infant-feeding training as "inadequate." Pediatricians and pediatric residents also have reported similar sentiments.
"Given the dearth of evidence for reason for solid food introduction by milk feeding type, it is not well understood why mothers of formula-fed infants were more likely than mothers of breastfed infants to cite a healthcare professional's advice as a reason for introducing solid foods earlier than recommended by the AAP," the authors said.
How mothers perceive their doctor's advice may indicate differences in clinician training, opinion, or counseling strategy, specific to formula-fed infants, the study said.
"It is possible that clinicians recommend earlier solid food introduction for formula-fed infants simply because they think that the solid food recommendation is specifically for breastfed infants, because much of the attention on infant feeding is focused on the goal of exclusive breastfeeding," the authors wrote.
New mothers self-reported their feeding preference when they discharged from the hospital.
The authors said theirs was the largest prospective study on U.S. babies and their feeding habits, but the study had limitations, most notably that the sample was not nationally representative, skewing to predominantly mothers who were white, middle income, and English speakers.
They noted that mothers in lower socioeconomic households were more likely to introduce solids earlier, the authors wrote. For 72 percent of Latina mothers in New York City receiving WIC benefits, baby crying was associated with a sign of hunger.
"It is reasonable to think that our sample may underestimate the prevalence of early solid food introduction," they said.