Plain Language Summary In the Burundian context, community members agree that large family sizes are difficult to maintain, yet use of family planning remains consistently low. This study explored the factors behind this low utilisation of family planning in two health districts located in the South of Burundi. The findings suggest that fear of side effects is the main reason for family planning non-utilization or discontinuation. The culture and religious beliefs in Rural Burundi also espouse large family sizes and among men, this is conceived as a sign of wealth, power, and respect. Lack of spousal communication and unequal gender relations in household also impedes women from contributing decisions on family planning. The onus on making decisions on contraceptive use lies on men, whom usually, have limited understanding of family planning methods. In improving coverage of family planning in these communities, capacity of the health system to provide quality, timely and people-driven family planning services should be strengthened. At the community level, the use of community health workers to deliver family planning services to the doorstep of community members could significantly increase uptake. Finally, men and religious leaders' involvement in promoting family planning use can contribute to reducing the impact of cultural and religious barriers to uptake. Background With a fertility rate of 5.4 children per woman, Burundi ranked as seventh country with the highest fertility rate in the world. Family planning is an effective way of achieving desirable family size, appropriate birth spacing and significant reduction in unintended pregnancies. Furthermore, family planning has been linked to improvements in maternal health outcomes. Yet, in spite of the overwhelming evidence on the benefits of family planning and despite high knowledge and free services, utilisation is low especially in rural communities with conservative people. Employing a mixed methods approach, this study first quantifies contraceptive prevalence and second, explores the contextual multilevel factors associated with low family planning utilisation among community members. Methods An explanatory sequential mixed study was conducted. Five hundred and thirty women in union were interviewed using structured and pre-tested questionnaire. Next, 11 focus group discussions were held with community members composed of married men and women, administrative and religious leaders (n = 132). The study was conducted in eighteen collines of two health districts of Vyanda and Rumonge in Bururi and Rumonge provinces in Burundi. Quantitative data was analysed with SPSS and qualitative data was coded and deductive thematic methods were applied to find themes and codes. Results The overall contraceptive prevalence was 22.6%. From logistic modelling analysis, it was found that women aged 25 to 29 (aOR 5.04 (95% CI 2.09-10.27 p = 0.038), those that have completed secondary school and having four or less children were significantly associated with use of family planning (aOR 1.72 (95%1.35-2.01) p = 0.002). Among factors why family planning was unused included experience with side effects and costs associated with its management in the health system. Religious conceptualisation and ancestral negative beliefs of family planning had also shaped how people perceived it. Furthermore, at the household level, gender imbalances between spouses had resulted in break in communication, also serving as a factor for non-use of family planning. Conclusion Given that use of family planning is rooted in negative beliefs emanating mainly from religious and cultural practices, engaging local religious leaders and community actors may trigger positive behaviours change needed to increase its use.
