Poi for Mama: a Pilot to Improve Maternal Microbiome and Gestational Diabetes Risk

This investigator-initiated, non-randomized pilot study evaluates whether daily consumption of fermented poi during pregnancy can improve maternal microbiome composition and reduce risk factors related to gestational diabetes mellitus (GDM). The intervention will be implemented during the second trimester. After a brief dietary washout period (avoiding poi and other fermented foods/beverages as specified in the protocol), eligible participants will receive fermented poi from a single source meeting food safety standards and will be instructed to consume one pound per day for 28 consecutive days. Participants will also receive culturally tailored nutrition education delivered via secure text messaging throughout the intervention period.

Participants will complete study assessments at enrollment, baseline, mid-point, end of intervention, long term follow-up in third trimester. Maternal microbiome outcomes will be assessed using self-collected vaginal swabs (with optional self-collection of oral and rectal swabs, if applicable). Samples will be labeled with a study identification code and returned to the study team using approved procedures. Study staff will collect anthropometrics and blood pressure at scheduled visits. Participants will complete questionnaires related to pregnancy characteristics, psychosocial and cultural factors, and intervention acceptability and feasibility. Dietary intake will also be assessed using a mobile food record and questionnaire-based measures during the study period. With participant authorization, information on GDM diagnosis and labor and delivery outcomes will be obtained from the participant's health care provider.

Study outcomes will be compared with matched controls derived from an existing cohort with similar characteristics and no or low poi consumption. Findings from this pilot study will inform feasibility, procedures, and effect-size estimates to support the design of a larger culturally grounded dietary intervention for GDM prevention.