A systematic review of behavioural interventions to increase maternal calcium intake

Pregnancy and lactation are a time when adequate calcium consumption is essential for the development of the fetus and to ensure the health of the mother. Over 50% of Canadian women of childbearing and rearing age fail to meet the recommended daily intake of calcium. Identification of effective behavioural intervention strategies for increasing calcium intake is needed within this specific population. This paper brings together all published behavioural interventions designed to increase calcium consumption in pregnant, lactating or post-partum mothers in a systematic review. Relevant studies were obtained through searches of MEDLINE, EMBASE, PsycINFO, CINAHL and the Cochrane Library with no date restrictions. Studies were evaluated using previously published criteria for evaluating calcium behaviour change interventions. This systematic literature review identified five behavioural calcium interventions conducted within this population. Three interventions aimed to improve overall dietary behaviours, the fourth aimed to promote breastfeeding (including increasing calcium consumption) and the fifth aimed to increase daily servings of yoghurt. Only one of the five interventions yielded large effect sizes, with a mean change of 954 mg of calcium per day post-intervention. The number of behavioural change techniques did not appear to be related to intervention efficacy. Only one study used a theoretical framework to guide the intervention. This review highlights the lack of research examining behaviour change interventions aimed at increasing calcium consumption in pregnant, lactating and post-partum women and provides practical suggestions for researchers wishing to intervene with this population in the future.