Challenging the utility of 24-hour recall of exclusive breast feeding in Japan

Abstract

Introduction WHO recommends exclusive breast feeding from birth to 6 months. However, to monitor populations, it recommends using the proportion of infants under 6 months who were exclusively breastfed during the previous 24 hours. To assess the usefulness of 24-hour recall, we (1) compared the prevalence of exclusive breast feeding measured by since-birth recall to the prevalence measured by 24-hour recall and (2) quantified each indicator’s association with WHO-recommended, well-established methods for in-hospital breastfeeding support. Methods We conducted two online surveys of mothers in Japan (total n=4247) who had a healthy singleton delivery in the previous 25 months. They reported on their breast feeding (a) from birth to 5 months; or (b) during the previous 24 hours, for those with infants under 5 months; or (c) both, for those who participated in the initial survey and also in the follow-up survey. All mothers also reported on their in-hospital support. The strength of each indicator’s association with provision of in-hospital support was quantified as the area under the curve (AUC). Results The prevalences of exclusive breast feeding by since-birth recall were 4.4% (first survey) and 2.5% (second survey). By 24-hour recall, the prevalence appeared to be 29.8%. More in-hospital support was moderately well associated with more exclusive breast feeding measured by since-birth recall: AUC 0.72 (95%CI 0.66 to 0.78). That association is consistent with the known benefits of in-hospital support. In contrast, when exclusive breast feeding was measured by 24-hour recall, its association with in-hospital support appeared to be extremely weak: AUC 0.59 (95% CI 0.54 to 0.65). Conclusion Using 24-hour recall substantially overestimates the prevalence of exclusive breast feeding since birth, and it conceals the benefits of in-hospital breastfeeding support. To monitor population achievement of exclusive breast feeding for the first 6 months, or to evaluate breastfeeding interventions, 24-hour recall of exclusive breast feeding should not be used alone.