Effectiveness of MMS Compared With IFS Among Pregnant Women in Bangladesh: an Experimental Study

Background Maternal undernutrition and micronutrient deficiencies remain highly prevalent in Bangladesh and contribute to maternal anaemia, low birth weight, preterm birth, and adverse neonatal outcomes. Although iron-folic acid supplementation (IFAS) is routinely provided through antenatal care services, it does not address the full spectrum of micronutrient deficiencies. Multiple micronutrient supplementation (MMS) has demonstrated superior outcomes in clinical trials; however, evidence from real-world programmatic settings in Bangladesh is limited. Methods and analysis This experimental study will be conducted from March 2025 to March 2026 through antenatal care platforms coordinated by the Institute of Public Health Nutrition (IPHN), with centralised laboratory analysis at the National Institute of Neurosciences \& Hospital (NINS\&H), Dhaka. Pregnant women will receive either MMS or IFAS according to routine service delivery. The primary outcome is infant birth weight. Secondary outcomes include maternal haemoglobin and micronutrient biomarkers, preterm birth, dietary diversity, and supplementation adherence. Quantitative data will be analysed using multivariable regression models in SPSS with adjustments for confounders and geographic clustering. A concurrent process evaluation will assess implementation, fidelity and acceptability. Ethics and dissemination Ethical approval has been obtained from the Institutional Review Board of NINS\&H. Written informed consent will be obtained from all participants. Study findings will be disseminated through peer-reviewed publications, policy briefs, and stakeholder engagement workshops.

Introduction Maternal undernutrition and micronutrient deficiencies remain major public health challenges globally, particularly in low- and middle-income countries such as Bangladesh. Inadequate intake of essential vitamins and minerals during pregnancy contributes substantially to adverse maternal and neonatal outcomes, including anaemia, low birth weight, preterm births, stillbirths, impaired foetal growth, and long-term developmental consequences for children \[1, 2\]. Pregnancy is a period of increased physiological demand that requires a higher intake of iron, folate, vitamin B12, vitamin D, iodine, zinc, and vitamin A to support placental development, erythropoiesis, immune regulation, and foetal organogenesis \[1\]. Failure to meet these requirements compromises both maternal health and foetal development, increasing risks that extend beyond the perinatal period. In Bangladesh, micronutrient deficiencies persist despite notable improvements in antenatal care coverage and maternal health indicators. National surveys and programme reports consistently demonstrate a high prevalence of anaemia, inadequate dietary diversity, and insufficient micronutrient intake among women of reproductive age, particularly in low-income and food-insecure households \[2, 9\]. Socioeconomic inequality, limited access to diverse diets, early marriage, and high fertility further exacerbate nutritional vulnerability during pregnancy. Poor maternal nutritional status is associated with obstetric complications, maternal morbidity, and adverse birth outcomes, while inadequate foetal nutrient supply has been linked to impaired neurodevelopment, weakened immune function, increased susceptibility to childhood illness, and faltering growth \[10\]. Since 2001, the Government of Bangladesh has implemented routine iron-folic acid supplementation as part of antenatal care services to reduce maternal anaemia and prevent neural tube defects \[3\]. While IFAS has contributed to improvements in iron status, its impact on broader pregnancy outcomes has been modest. IFAS addresses only two micronutrients and does not account for the multiple concurrent deficiencies commonly observed among pregnant women in low-resource settings. As a result, many women are deficient in other essential micronutrients that play a critical role in foetal growth and development \[11\]. Multiple micronutrient supplementation, particularly the United Nations International Multiple Micronutrient Antenatal Preparation (UNIMMAP) formulation, was developed to address these gaps by providing a balanced combination of 15 essential vitamins and minerals. Accumulating evidence from randomised controlled trials and systematic reviews indicates that MMS provides superior benefits compared with IFAS alone. A Cochrane review reported significant reductions in low birth weight, small-for-gestational-age births, and maternal anaemia among women receiving MMS \[4\]. An individual participant data meta-analysis of 1 trial.show_full_description

Inclusion Criteria: * Participants will be eligible if they meet all of the following: 1. Confirmed pregnancy, preferably in the first trimester, with singleton pregnancy where feasible. 2. Permanent residence within the selected study catchment areas and ability to remain in the study area throughout follow-up. 3. Enrollment in IPHN-supported antenatal care or supplementation programs. 4. Nutritional vulnerability identified through screening indicators (eg, MUAC, BMI, or hemoglobin). 5. Willingness to receive MMS or IFAS supplementation as assigned by routine service delivery platforms. 6. Provision of written informed consent (thumbprint with witness for illiterate participants). 7. Planned facility-based delivery or verifiable delivery location. Exclusion Criteria: * Participants will be excluded if any of the following apply: 1. Withdrawal of informed consent at any stage. 2. Diagnosed chronic medical conditions likely to influence pregnancy outcomes or nutritional biomarkers (eg, diabetes, hypertension, thyroid disorders, thalassemia). 3. Planned relocation outside the study area before completion of follow-up. 4. High-risk pregnancy requiring specialized tertiary care at enrollment. 5. Participation in another nutrition intervention or clinical trial during the study period. 6. Multiple gestation pregnancies (eg, twins).