Chemerin is an adipokine and plays a role in oocyte development by taking part in autocrine and paracrine signaling. It may influence the results of in vitro fertilization therapy (IVF) through its receptors on the follicles. We aimed to investigate serum and follicular fluid chemerin levels and its relationship with IVF outcomes in patients with reduced ovarian reserve. The study included a total of 100 patients, 50 of them had reduced ovarian reserve and 50 of them were control. Serum and follicular fluid (FF) chemerin level, AMH (Anti-Müllerian Hormone) and basal hormone levels, antral follicle counts and IVF outcomes were recorded. Mean serum and FF chemerin levels were found to be lower in patients with reduced ovarian reserve than controls although statistical significance was not detected. A significant positive correlation was found between serum chemerin levels and BMI, number of IVF attempts and cycle length. We also observed a significant positive correlation between FF chemerin and the number of IVF attempts. The beta-hCG positivity rate in the study group (24%) was significantly lower than the control group (50%) (p=0.007). In the study group, ongoing pregnancy rate (8%) was significantly lower than the control group (64%) (p=0.001). It is the first study comparing chemerin levels in patients undergoing IVF treatment due to reduced ovarian reserve and controls (male factor and unexplained infertility). We can not show the statistical significance although we found the mean serum and FF chemerin levels are lower than the controls. Chemerin may play a role in the pathophysiology of reduced ovarian reserve. [ABSTRACT FROM AUTHOR]