iarjcmbIARJCMBIARJCMB2789-6005https://doi.org/10.47310/iarjcmb.2025.v05i02.002Evaluation of Homocysteine as a Biomarker of Oxidative Stress and Its Association with Vitamin C in Obese Women with Polycystic Ovary SyndromeMohammedNaji QasimNoorKhalid SalehAl-Hadi University College, Department of Medical Laboratory Technology, Baghdad, IraqDepartment of Obstetrics and Gynaecology, College of Medicine, University of Diyala, Diyala, IraqPolycystic ovarian syndrome (PCOS) is a prevalent endocrine-metabolic condition impacted by environmental factors and heredity. Elevated homocysteine (HCY) levels in PCOS contribute to oxidative stress by depleting glutathione, inhibiting antioxidant enzymes and inducing cellular damage, which negatively affects fertility and exacerbates insulin resistance and hyperandrogenism. Vitamin C (ascorbic acid), a key water-soluble antioxidant, reduces oxidative stress by shielding carbohydrates, nucleic acids and lipids from degradation resulting from free radicals and reactive oxygen species created during metabolism and immunological processes. The aim of this study is to compare homocysteine and vitamin C levels and explore their correlation in obese women with polycystic ovary syndrome. The present case-control research was conducted in the infertility centre at Al-Batool Teaching Hospital in Diyala Governorate, Iraq, from April 2024 to January 2025. The present study comprised one hundred thirty-two ladies aged 18 to 40 years. The participants were divided into two groups: 66 PCOS patients and 66 women as healthy controls.  A competitive enzyme-linked immunosorbent test examined the amounts of serum homocysteine and vitamin C. The research results demonstrated considerably higher serum homocysteine concentrations inside the PCOS group compared to the control group.  The concentrations of vitamin C within the PCOS group were considerably reduced compared to that in the non-PCOS group, which revealed a significant negative correlation between serum homocysteine levels and vitamin C (r = -0.790, p< 0.0001) in the PCOS group. Polycystic Ovary Syndrome patients have increased homocysteine and reduced vitamin C, with a substantial negative connection. Obesity worsens both conditions in these patients.