Infant bottle propping among a low-income urban population in Mexico.

The prevalence of bottle propping (permitting an infant to drink from a bottle unattended) and the determinants of this practice at 1 week and 4 months of life were studied in a selected sample of urban women in Hermosillo, Mexico. The sample (n = 165) consisted of mothers planning to breast-feed who gave birth to healthy infants at one of two public hospitals. Data were obtained by interviewing women shortly before they were discharged from the hospital and at about 1 week and 4 months postpartum. Among those mothers giving liquid breast milk substitutes to their infants, the percentage practicing bottle propping increased from 27% at 1 week (n = 20/74) to 67% at 4 months (n = 87/130). Women who practiced bottle propping at 1 week were significantly more likely to continue this practice at 4 months. Bottle propping was significantly more common, both at 1 week and 4 months, among women who had completely weaned their infants than among those who were still combining breast and formula feeding. Multivariate logistic regression indicated that 1-week risk factors for bottle propping were low socioeconomic status, being a multiparous single mother, and being a young mother (< or = 18 years old) with a female infant, while 4-month risk factors were complete weaning, delivery in a "nursery" (versus a "rooming-in") hospital, and lack of support by the mother's partner for breast-feeding. While the possible health risks associated with early bottle propping have not been well defined, the extent of the practice observed in this study suggests that such risks deserve further investigation.