The effect of breastfeeding on the bone mass of post-menopausal women: A systematic review of observational studies

Abstract

Objectives: to evaluate the effect o breastfeeding on the bone mass of post-menopausal women. Methods: a systematic review of observational studies was carried out. The literature was searched using the Lilacs, Medline and Scopus bibliographical databases, in June 2015, with no restrictions as to year of publication. To be included in the review, the article must have investigated the history of breast-feeding and post-menopausal bone mass and refer-ences were checked to unearth further studies. Two reviewers independently extracted data and evaluated the potential bias of the studies. Results: 34 studies were selected, six of which (26.5%) found that breastfeeding significantly increased bone mass and 15 (44%) came up with the opposite finding. There was much variation among the studies as to study population, measurement of exposure and location of bone mass measurement, making it difficult to compare the results. Conclusions: the marked heterogeneity of the studies made it difficult to conclude the direction of association between breastfeeding and bone mass in post-menopausal women. More methodologically rigorous studies are needed to assess this issue of great importance for clinical practice and public health.