Acceptability of Antenatal Multiple Micronutrient Supplementation (MMS) Compared to Iron and Folic Acid (IFA) Supplementation in Pregnant Individuals: A Narrative Review.

: Antenatal multiple micronutrient supplementation (MMS) improves birth outcomes more effectively than iron and folic acid (IFA) supplementation alone. However, the acceptability of MMS among pregnant individuals, a critical factor for adherence and program success, remains poorly defined and inconsistently assessed. This narrative review proposes a comprehensive definition of "acceptability" in the context of nutritional supplementation and evaluates the evidence on the acceptability of MMS compared to IFA in low- and middle-income countries (LMICs). : We conducted a systematic literature search across Embase, Medline, and Scopus to identify studies (including grey literature) reporting on acceptability-related outcomes for MMS versus IFA among pregnant individuals. Studies exploring dimensions such as organoleptic properties, ease of consumption, side effects, cultural appropriateness, and socioeconomic factors were included. : Out of 1056 screened studies, five informed a novel multi-dimensional definition of acceptability. Six studies assessed acceptability-related characteristics. MMS was generally accepted across most organoleptic domains. Most studies reported fewer or comparable adverse side effects for MMS as compared to IFA. Studies consistently reported more perceived benefits for MMS than IFA. Facilitating factors included trust in health professionals, free provision, and family support. Barriers included poor taste or smell, fear of side effects, misconceptions, cost, and lack of family support. : Antenatal MMS is widely acceptable in LMICs. Addressing socio-cultural, sensory, and socioeconomic factors is essential to increase uptake and adherence. This review provides a clear, standardized definition of acceptability to guide future research and inform effective program design.