Infant feeding bottle design, growth and behaviour: results from a randomised trial

Abstract Background Whether the design of an anti-vacuum infant feeding bottle influences infant milk intake, growth or behavior is unknown, and was the subject of this randomized trial. Methods Subjects 63 (36 male) healthy, exclusively formula-fed term infants. Intervention Randomisation to use Bottle A (n = 31), one-way air valve: Philips Avent) versus Bottle B (n = 32), internal venting system: Dr Browns). 74 breast-fed reference infants were recruited, with randomisation (n = 24) to bottle A (n = 11) or B (n = 13) if bottle-feeding was subsequently introduced. Randomisation stratified by gender and parity; computer-based telephone randomisation by independent clinical trials unit. Setting Infant home. Primary outcome measure infant weight gain to 4 weeks. Secondary outcomes (i) milk intake (ii) infant behaviour measured at 2 weeks (validated 3-day diary); (iii) risk of infection; (iv) continuation of breastfeeding following introduction of mixed feeding. Results Number analysed for primary outcome Bottle A n = 29, Bottle B n = 25. Primary outcome There was no significant difference in weight gain between randomised groups (0-4 weeks Bottle A 0.74 (SD 1.2) SDS versus bottle B 0.51 (0.39), mean difference 0.23 (95% CI -0.31 to 0.77). Secondary outcomes Infants using bottle A had significantly less reported fussing (mean 46 versus 74 minutes/day, p Breast-fed reference group There were no significant differences in primary or secondary outcomes between breast-fed and formula fed infants. The likelyhood of breastfeeding at 3 months was not significantly different in infants subsequently randomised to bottle A or B. Conclusion Bottle design may have short-term effects on infant behaviour which merit further investigation. No significant effects were seen on milk intake or growth; confidence in these findings is limited by the small sample size and this needs confirmation in a larger study. Trial registration Clinical Trials.gov NCT00325208.