Objectives Low birthweight significantly contributes to neonatal mortality, morbidities and psychosocial debilities throughout the course of life. A large proportion of infants (36–55%) in Bangladesh is born with low birthweight. Nutritional status of women during pregnancy is critical for optimal growth and development of the fetus. Nutrition education has been found to improve maternal nutritional status. Our study aims to determine whether nutrition education with a practical demonstration during pregnancy is an effective intervention for improving the birthweight of infants compared with standard nutrition education only.

Methods and analysis We will conduct a community-based cluster randomised controlled trial in one rural district of Bangladesh. Treatments will be allocated evenly between the study clusters (n=36). Participants in the intervention clusters receive ‘balanced plate nutrition education’ with a practical demonstration from community health workers 4–7 times throughout their entire pregnancy, starting from the first trimester. The control clusters will receive standard nutrition education delivered by public and other healthcare providers as per ongoing antenatal care protocol. Our sample size would be 900 pregnant women to determine 100 g differences in mean birthweight, considering 5% type 1 error, 80% power and an intra-cluster correlation coefficient of 0.03. The primary outcome of the trial is birthweight of the infants and the secondary outcomes include daily caloric intake and dietary diversity score among the pregnant women. Outcomes will be measured at enrolment, third to ninth month of gestation (monthly) and at delivery. Community health workers blinded to the study hypothesis will collect all data.