en <div style=text-align: justify;><strong>Aims:</strong> The high prevalence of Cesarean section (CS) is a global health concern globally, especially in Iran. The current study aimed to evaluate the effect of a Theory of Planned Behavior (TPB) based educational intervention on preventing elective cesareans.<br> <strong>Materials & Methods:</strong> An interventional study (NCT02929875) was conducted on a sample of 100 nulliparous pregnant women attending health care centers in Kermanshah, Iran, 2016. Women were randomly selected and assigned into either intervention or control groups on a 1:1 basis. The intervention group received a theory-based (Theory of Planned Behavior) health education intervention, while the control group received only standard care. A questionnaire containing items on TPB constructs, including attitude, subjective norms, perceived behavioral control, and intention, was used to collect baseline and 1-month follow-up assessments. Each woman also received a phone call after childbirth to record their delivery method. Data were analyzed using SPSS version 15 at a significance level of p<0.05. The paired t-test, the independent t-test, the chi-square, and ANCOVA were used for data analysis.<br> <strong>Findings:</strong> The results revealed significant differences in scores of attitude, subjective norms, perceived behavioral control, and behavioral intention in the intervention group before and after the intervention (p<0.05). Additionally, the intervention group chose elective cesarean less than the control group (p<0.05). The risk of having an elective cesarean section in the intervention group was about one-fifth of the control group (RR= 0.21; CI=0.4197 to 0.0018).<br> <strong>Conclusion:</strong> According to this randomized control trial results, the TPB-based education improved the TPB constructs and NVD rates by providing education to women and their close friends or relatives during pregnancy.</div> Health Behavior,Health Education,Natural Childbirth,Cesarean Section, 61 66 http://hehp.modares.ac.ir/browse.php?a_code=A-10-59106-1&slc_lang=en&sid=4 B. Soheili 1003194753284600208838 1003194753284600208838 No Department of Public Health, School of Health, Ilam University of Medical Sciences, Ilam, Iran A. Mirzaei 1003194753284600208839 1003194753284600208839 No Department of Public Health, School of Health, Ilam University of Medical Sciences, Ilam, Iran K. Sayehmiri 1003194753284600208840 1003194753284600208840 No Department of Biostatistics, School of Health, Ilam University of Medical Sciences, Ilam, Iran A. Montazeri 1003194753284600208841 1003194753284600208841 No Mental Health Research Group, Health Metrics Research Centre, Iranian Institute for Health Sciences Research (ACECR), Tehran, Iran M. Araban 1003194753284600208842 1003194753284600208842 No Department of Health Education and Promotion, Public Health School, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran Z. Ghazanfari ghazanfari-z@medilam.ac.ir 1003194753284600208843 1003194753284600208843 Yes Department of Public Health, School of Health, Ilam University of Medical Sciences, Ilam, Iran