Introduction Studies show, malnourished women of childbearing age with environmental enteric dysfunction (EED) exhibit small intestinal enteropathy resembling that in malnourished children residing in the same community. However, currently there are no universally accepted protocols for validation of these facts. Our current protocol is designed to better understand the mechanism of transmission of the microbiota of mothers with EED to their children perpetuates intergenerational undernutrition. We plan to compare the small intestinal (SI) and fecal microbiota along with plasma, duodenal, and fecal proteomes/ metabolomes and histopathologic evidence of EED in non-pregnant women with and without malnutrition. We also plan to see and compare the effect of microbiota-directed balanced energy protein (MD-BEP) supplementation on these biological parameters between malnourished non-pregnant and pregnant women.

Methods and analysis This is a community-based intervention study where pregnant women and non-pregnant women of reproductive age (18-35 years) will be screened through household surveys from the Bauniabadh and adjacent slum area of Mirpur, Dhaka (pregnant and non-pregnant cohorts, n=90 each). Using Body Mass Index (BMI), both the groups will be categorized into undernourished (BMI <18.5kg/m2, n=60 each with pregnant and non-pregnant cohort) and well-nourished (BMI >20-24.9 kg/ m2, n=30, each with pregnant and non-pregnant cohort). Upper gastro-intestinal (UGI) endoscopy will be performed on non-pregnant women (both well-nourished and undernourished cohorts) and biopsy samples will be collected for diagnosis of environmental enteric dysfunction (EED) by histopathological scoring. We will compare the small intestinal (SI) and fecal microbiota and the plasma, duodenal, and fecal proteomes/ metabolomes of the undernourished non-pregnant cohort with histopathologic evidence of EED with the well-nourished non-pregnant cohort with no histopathologic evidence of EED (Aim IA). Furthermore, we will perform an intervention study (Aim IB). The undernourished non-pregnant cohort will be randomized into two groups (n=30/arm) and receive daily dietary supplementation with either shelf-stable microbiota-directed balanced energy protein (MD-BEP) or ready-to-use supplementary food balanced energy protein (RUSF-BEP) for 90 days. After cessation of the intervention they will be further followed up for another 270 days and biological samples will be collected at scheduled time points. The well-nourished non-pregnant cohort will not receive any nutritional intervention will serve as a reference control group. The undernourished pregnant cohort will also be randomly (n=30/arm) assigned to receive either MD-BEP or RUSF-BEP daily for 6 months until the child birth and thereafter for 3 months and followed up for another 9 months. During this period anthropometry will be measured and biological samples including fecal and plasma samples will be collected from the mothers and their infants in scheduled time points. Anthropometric, socio-demographic and laboratory assay data will be compared between the groups and candidate EED biomarkers will be correlated with nutritional status, histological analyses and score of EED, plus assessments of microbial community structure will be examined.

Ethics and dissemination Ethics approval was obtained from the Ethical Review Committee of icddr,b (protocol no: PR-22117; Version 1.2; 29 November 2022). Results of this study will be submitted for publication in peer-reviewed journals.

The authors have declared no competing interest.

ClinicalTrials.gov ID: NCT05862363. Registered on 08 February 2023. https://clinicaltrials.gov/study/NCT05862363

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Ethical Review Committee of icddr,b approved the protocol (protocol no: PR-22117 Version 1.2 29 November 2022)

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No datasets were generated or analysed during the current study. All relevant data from this study will be made available upon study completion.