The Effect of Maternal Dadiah (Minangkabau Yogurt) Supplementation During Pregnancy on Child Growth, Gut Microbiota Proportion and the Level of Secretory Immunoglobulin A, in West Sumatra: A Randomised Clinical Trial

The study was carried out on pregnant women in four Public Health Center (PHC) areas in Padang Panjang, West Sumatra, Indonesia. They were screened for inclusion and exclusion criteria. Once eligibility was confirmed, pregnant women were randomly allocated to intervention or control groups. The details of the study protocol were explained, and voluntary written consent was obtained.

General information about the mother was collected and a general physical examination was assessed. The intervention started at about 10-20 weeks of gestation and continued until just before the time of delivery. Subjects took the study supplements concurrently with the government's dietary supplementation program. In each home visit, the remaining supplements from the previous visit were counted and documented in the pudding checklist form. Details of symptoms or illnesses during consumption of dadiah pudding will be reported either by participants directly contacting field officers, study staff, or during weekly visits and will be recorded and documented in the case report form. In the third trimester, subjects received healthy food, breastfeeding practices, and child development education to support mothers in maintaining their nutritional status, preparing exclusive breastfeeding, and optimizing child development.

Healthy babies born to mothers will be the focus of this study and followed up until the age of three months to assess their growth. The information includes the baby's health history after birth, anthropometric measurements, nutritional intake, and breastfeeding practices which are measured repeatedly in the first, second, and third months. The collection of breast milk and baby feces is carried out in the first week and third month after the baby is born.

The sample size was calculated taking into account all outcome variables including the proportion of gut microbiota, levels of IgA secretion in breast milk and infant feces, and child growth, with the independent variable being maternal supplementation during pregnancy.

Data quality assurance is carried out through training starting from the period of data collection and supervision during and after data collection, including the data analysis process. This included training for enumerators, subjects and using a validated questionnaire for a group of subjects representing similar characteristics for this study. Data input and cleaning process will use excel and SPSS while for food intake data using NutriSurvey 2007. Data entry will be carried out by data collection officers after data collection. The data cleaning process includes removing outliers and regrouping multiple results that have similar meanings. The data will be interpreted as mean ± standard deviation if the data is normally distributed and the median (min-max) if the data is not normally distributed. Statistical analysis using SPSS 20 and data will be analyzed using univariate and bivariate analysis. Univariate analysis is used to describe characteristics and socio-demographics, medical history, pregnancy, and obstetric profiles of pregnant women. Numerical variables between groups will be analyzed using an Independent sample t-test if the data has normal distribution or the Mann Whitney test if the data distribution is not normal. Categorical variables between groups will be analyzed using Chi-square or Fisher test. Differences between birth and 3 months old follow up will be analyzed using Dependent t-tests if the data distribution has normal distribution or Wilcoxon test if the data distribution is not normal.