To examine whether women’s knowledge of pregnancy-related risks and family support received during pregnancy are associated with adherence to maternal iron–folic acid (IFA) supplementation.

Secondary data analysis of the 2002–03, 2007 and 2012 Indonesia Demographic and Health Survey. Analysis of the association between factors associated with adherence (consuming ≥90 IFA tablets), including the women’s knowledge and family support, was performed using multivariate logistic regression.

National household survey.

Women (n 19 133) who had given birth within 2 years prior to the interview date.

Knowledge of pregnancy-related risks was associated with increased adherence to IFA supplementation (adjusted OR=1·8; 95 % CI 1·6, 2·0), as was full family (particularly husband’s) support (adjusted OR=1·9; 95 % CI 1·6, 2·3). Adequate antenatal care (ANC) visits (i.e. four or more) was associated with increased adherence (adjusted OR=2·2; 95 % CI 2·0, 2·4). However, ANC providers missed opportunities to distribute tablets and information, as among women with adequate ANC visits, 15 % reported never having received/bought any IFA tablets and 30 % had no knowledge of pregnancy-related risks. A significant interaction was observed between family support and the women’s educational level in predicting adherence. Family support significantly increased the adherence among women with <9 years of education.

Improving women’s knowledge of pregnancy-related risks and involving family members, particularly the husband and importantly for less-educated women, improved adherence to IFA supplementation. ANC visit opportunities must be optimized to provide women with sufficient numbers of IFA tablets along with health information (especially on pregnancy-related risks) and partner support counselling.