Vol.:(0123456789) SN Comprehensive Clinical Medicine (2023) 5:197 https://doi.org/10.1007/s42399-023-01538-5 ORIGINAL PAPER Investigation of Breast Cancer Risk Factors in the Imam Hossein and Shohada‑E Tajrish Hospitals of Tehran in 2019–2022: A case–control study Hanieh Bayat 1  · Sima Nazarpour 2  · Robab Anbiaee 3 Accepted: 26 July 2023 © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2023 Abstract Breast cancer is one of the most common cancers and causes of death worldwide. Various factors such as family history, lifestyle, the reproductive and social factors can infuence the risk of breast cancer. In this study, we investigated breast cancer risk factors in Iranian women. The aim of this study was to investigate diferent risk factors for breast cancer. In this case–control study conducted in two hospitals in Tehran, 250 women with breast cancer were compared with 250 women without breast cancer as a control group. Data collection was done through checklists with questions about lifestyle, repro- ductive and social factors. Logistic regression was used. The level of statistical signifcance was set at P < 0.05 for all the tests. Our results showed stress and mental pressure [OR:1.77 (95% CI:1.51–2.09) (P < 0.001)], HRT [OR: 15.07 (95% CI: 2.46–289.68) (P < 0.001)], increasing age [OR:1.09 (95% CI:1.07–1.11) (P < 0.001)], increasing gravida [OR:2.68 (95% CI: 2.09–3.48) (P < 0.001)], increasing live birth number [OR:1.04 (95% CI:2.19–3.74) (P < 0.001)], being married [OR: 8.58 (95% CI: 4.36–18.92) (P < 0.001)], menopause [OR:2.95 (95% CI: 1.97–4.47) (P < 0.001)], abortion history [OR:2.54 (95% CI:1.69–3.86) (P < 0.001)] and prolonged breastfeeding [OR:2.01 (95% CI:1.63–2.49) (P < 0.001)] increase the chance of breast cancer. On the other hand, increasing education level [OR: 0.34 (95% CI:0.28–0.42) P < 0.001] and regular menstrual cycles [OR:0.61 (95% CI:0.39–0.95) (P = 0.030)] get less breast cancer. Our study demonstrated that stress and mental pres- sure, increasing age, and menopause status increased the risk of breast cancer; in contrast, increasing education level and regular menstrual cycles decreased breast cancer risk. Keywords Breast cancer · Risk factors · Reproductive · Stress · Gravida Abbreviations BC: Breast cancer HRT: Hormone replacement therapy OCP: Oral contraceptive pills BMI: Body mass index ICC: Intraclass correlation coefcient HPA: Hypothalamic–pituitary–adrenal axis Introduction Breast cancer is one of the most common cancers and one of the most common causes of death worldwide. Studies showed every 3 min, one woman is diagnosed with breast cancer in the world which means a total of one million cases per year [1–3]. According to the WHO (2020), 2.3 million women were diagnosed with breast cancer, and 685,000 people worldwide died of it [4]. It is the second most com- mon cancer in developed countries, and its prevalence is Topical Collection on Medicine. * Sima Nazarpour snazarpour@gmail.com Hanieh Bayat hanieh.bayat98@gmail.com Robab Anbiaee Anbiaee-mm@sbmu.ac.ir 1 Department of Anatomical Sciences and Cognitive Neuroscience, Faculty of Medicine, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran and Mens Health and Reproductive Healt Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran 2 Associate professor, Department of Midwifery, Varamin-Pishva Branch, Islamic Azad University, Tehran, Iran 3 Department of Radiation Oncology, Imam Hossein Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran