Tehran University of Medical Sciences Iranian Journal of Public Health 2251-6085 53 7 2024 07 07 1621 1628 Fateme Sheikholmolooki Department of Nutrition, Health and Statistics Surveillance Research Center, Science and Research Branch, Islamic Azad University, Tehran, Iran Abolghassem Djazayeri Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran Behnood Abbasi Department of Nutrition, Health and Statistics Surveillance Research Center, Science and Research Branch, Islamic Azad University, Tehran, Iran 2022 12 05 2023 08 16 Background: Cesarean section (CS) is one of the most important pregnancy concerns in the world. Increased inflammation is associated with increased risk factors for cesarean section. Diet plays a major role in reducing inflammation. This study aimed to investigate the relationship between dietary inflammatory index (DII) and the risk of Cesarean section in Tehranian women. Methods: This case-control study included 390 pregnant women in Tehran, Iran between 2020 and 2021 at their initial visit to pregnancy clinics, selected by a cluster sampling method. Dietary intakes were determined using valid reliable questionnaires and DII was calculated. Weight, height, and waist circumference were also measured. Results: The mean age of the subjects was 28.5 yr (± 5.02) and weight, body mass index (BMI) and waist circumference (WC) in the case group with a higher DII were higher. Odds ratio (OR) of cesarean section in DII quartiles was statistically significant. Confounding factors including age, BMI and total energy intake were adjusted in the first model and weight, waist circumference, physical activity and supplements in the second model and the relationship remained significant (P<0.001). Conclusion: High scores of dietary inflammatory index, possibly through an increase in inflammatory factors, can increase the chances of having a cesarean section. https://ijph.tums.ac.ir/index.php/ijph/article/view/30583 https://ijph.tums.ac.ir/index.php/ijph/article/download/30583/8294