This prospective cohort study investigates the association between metabolic disturbances and reproductive dysfunction in women with idiopathic infertility and recurrent pregnancy loss (RPL). Conducted at the Perinatal Centre of Grozny from 2022 to 2025, the study involved 240 women allocated into three groups: Group 1 (n=120) with idiopathic infertility/RPL, Group 2 (n=60) with tubal factor infertility, and a control Group 3 (n=60) of fertile women. All participants underwent a comprehensive assessment, including anthropometric measurements, hormonal profiling, evaluation of insulin resistance (HOMA-IR, QUICKI), adipokine status (leptin, adiponectin), oxidative stress markers (MDA, SOD), and transvaginal ultrasonography. The results revealed a distinct metabolic phenotype in Group 1, characterized by significantly higher BMI, waist circumference, and markers of insulin resistance (HOMA-IR: 3.8 vs. 1.4 in controls, p<0.001). Profound adipokine dysregulation was evident, with a leptin/adiponectin ratio exceeding 4.95 compared to 1.10 in Group 3 (p<0.001). Concurrently, elevated oxidative stress was observed (MDA: 6.85 nmol/mL vs. 4.55, p<0.001). These metabolic alterations correlated with impaired reproductive markers, including a higher LH/FSH ratio, hyperandrogenemia, reduced antral follicle count, and significantly poorer endometrial receptivity (endometrial thickness: 8.1 mm vs. 10.2 mm; three-line endometrium incidence: 56.7% vs. 95.0%). In contrast, Group 2 parameters aligned with healthy controls. The findings strongly suggest that insulin resistance, adipokine imbalance, and oxidative stress are integral pathophysiological components of idiopathic infertility and RPL, advocating for their recognition as a "metabolic" subtype of reproductive failure. Integrating metabolic screening into standard diagnostic protocols is crucial for targeted preconception management.
