Oral Health Promotion Intervention During Pregnancy: Bangladesh Perspective
Phase: NA
Conditions: Pregnancy, Periodontal Diseases, Oral Hygiene, Oral Health
Sponsor: Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh

Education-Based Oral Health Promotion Intervention During Pregnancy: Implementation 
Protocol in Bangladesh 
 
                                                       IRB No: BMU/2026/1575                         Date: 14/02/2026 
 
PI: Prof. Md Atiqul Haque, PhD, MBBS 
Bangladesh Medical University  
 
In Bangladesh, over 95% of pregnant women suffer from gum disease, yet oral health is rarely 
part of regular pregnancy check-ups. This study tests a new "Integrated Oral Health Promotion 
Package" to see if adding dental education to existing ANC (Upazila Health Complexes) 
improves the health and habits of expectant mothers. 
Objectives 
To assess the effect of the education-based oral health promotion intervention, compared with 
usual care, on oral health behaviours and knowledge among pregnant women at 12 weeks. 
Design, and methods 
This study is designed as a cluster randomized controlled implementation trial evaluating an 
education-based oral health promotion model for pregnant women in Bangladesh. The study is 
conducted in eight Upazila Health Complexes (UHCs) across eight administrative divisions. This 
protocol and all recruitment materials have been approved by the IRB of Bangladesh Medical 
University. Any future amendments to the protocol or study sites will be submitted for board 
approval before implementation. To prevent treatment contamination, staff at intervention sites 
will not rotate to control sites, and clinical examiners remain blinded to the 1:1 cluster allocation 
throughout the 12-week follow-up. 
Participant Enrollment and Power 
A total of 688 pregnant women (86 per cluster) with a gestational age ≤24 weeks will be 
recruited. The sample size provides 80% power at a 5% significance level to detect a 20% 
improvement in the primary outcome, assuming a 1.5 design effect (ICC = 0.05) and a 20% 
attrition rate. 

Statistical Analysis Plan (SAP) and Assumption Verification 
Analysis follows the Intention-to-Treat (ITT) principle using Mixed-Effects Linear Regression 
for clinical scores (OHI-S) and Mixed-Effects Logistic Regression for binary behavioral 
outcomes. The UHC is included as a random effect to account for clustering. 
• 
Verification of Assumptions: To meet PRS requirements for statistical transparency, the 
normality of continuous outcomes will be verified using Shapiro-Wilk tests and Q-Q 
plots. If assumptions are violated, non-parametric methods or log-transformations will be 
employed. 
• 
Multiple Testing: To account for testing multiple variables (OHI-S, Knowledge Score, 
and Behavior), a Bonferroni correction will be applied to the p-values. 
• 
Missing Data: If missingness exceeds 5%, Multiple Imputation (m=20) will be used to 
handle incomplete data. 
Outcome Measures 
The primary clinical endpoint is the Oral Hygiene Index–Simplified (OHI-S), measuring debris 
and calculus on six tooth surfaces (score 0–6). Secondary endpoints include a 10-item validated 
Knowledge Score and self-reported behavioral changes in twice-daily brushing frequency from 
baseline to 12 weeks.