Relationship between resistin and IL-23 levels in follicular fluid in infertile patients with endometriosis undergoing IVF-ET

Background. Endometriosis (EM) interferes with the reproductive process and affects the success rate of in vitro fertilization (IVF). Inflammatory cytokines are suggested to play a role in infertility in patients with EM. Objectives. In this study, we aimed to investigate the relationship between resistin and interleukin 23 (IL-23) levels in follicular fluid (FF) and serum together with the severity of endometriosis and in vitro fertilization/ embryo transfer (IVF-ET) outcome. Material and methods. Samples from 116 infertile women were studied using enzyme-linked immunosorbent assay (ELISA). The study group consisted of 76 infertile patients diagnosed with EM (40 with stages I-II and 36 with stages III-IV) undergoing IVF-ET. The control group included 40 women with tubal factor infertility. FF and serum samples were collected on the day of follicle aspiration and hCG administration, respectively. Results. The serum and FF resistin levels were significantly higher in the EM group than in the control group (p-value < 0.05). The FF resistin and IL-23 levels were significantly higher in EM stages III-IV than in stages I-II (p-value < 0.05), and the serum resistin and IL-23 levels were also significantly (p-value < 0.01) higher in stages III-IV than in stages I-II. The E-2 level on the day of hCG administration and the implantation rate were both significantly lower in the EM group than in the control group. However, there were no differences in the Gn duration and dose, and the cleavage, implantation and clinical pregnancy rates between the 2 groups. Conclusions. Our results suggest that patients with EM exhibit increased resistin level in FF and serum. Advanced EM may contribute to infertility via decreased embryo implantation rates because of inflammation and immune rejection. No influence was observed on pregnancy outcomes after IVF-ET.