Mixed-Methods Systematic Review of Behavioral Interventions in Low- and Middle-Income Countries to Increase Family Support for Maternal, Infant, and Young Child Nutrition during the First 1000 Days.

Fathers, grandmothers, and other family members' influence on maternal, infant, and young child nutrition (MIYCN) is widely recognized, yet synthesis of the effectiveness of engaging them to improve nutrition practices during the first 1000 d is lacking. We examined the impact of behavioral interventions to engage family members in MIYCN in low- and middle-income countries through a mixed-methods systematic review. We screened 5733 abstracts and included 35 peer-reviewed articles on 25 studies (16 with quantitative and 13 with qualitative data). Most quantitative studies focused on early breastfeeding, primarily engaging fathers or, less often, grandmothers. Most found positive impacts on exclusive breastfeeding rates and family members' knowledge and support. The few quantitative studies on complementary feeding, maternal nutrition, and multiple outcomes also suggested benefits. Qualitative themes included improved nutrition behaviors, enhanced relationships, and challenges due to social norms. Interventions engaging family members can increase awareness and build support for MIYCN, but more rigorous study designs are needed. This systematic review is registered at PROSPERO as CRD42018090273, https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=90273.