Breastfeeding up to two years of age or beyond and its influence on child growth and development: a systematic review

A systematic review was undertaken to identify studies describing the global prevalence of breastfeeding up to two years of age or beyond and its effects on child growth and development. The MEDLINE and LILACS databases were searched without any language or date restrictions, retrieving 3,561 titles. All retrieved titles, 453 abstracts and 49 full-text articles were read. Articles with maximum breastfeeding duration of over two years were included. An analysis was carried out of 19 articles that met the inclusion criteria resulting in a combined prevalence of breastfeeding at two years of age of 33 % (95% CI: 0.23; 0.42). Increasing trends towards breastfeeding up to two years of age or beyond were observed in the past decades in South Asia. The six studies analyzing the effects of breastfeeding up to two years of age or beyond on child growth showed contradictory results. No association was found with child development. It is concluded that evidence on the medium-term effects of breastfeeding up to two years of age or beyond is scarce and contradictory. Hence, further research is needed regarding this practice.