The investigators explore whether inflammatory factors and infections in collected samples are altered in fertility issues and if they can predict pregnancy outcomes. The investigators focus on pro- and anti-inflammatory markers, such as cytokines, metabolic parameters (e.g., blood lipids, hormones, bile acids), and viral infections (e.g., HPV, herpesviruses). A standard blood panel is also performed. Fertility issues are rising due to aging, infections, environmental toxins, and lifestyle factors (e.g., BMI, diabetes). Fertilization and implantation involve complex interactions between the egg, sperm, embryo, and endometrium, which can be disrupted by inflammatory processes from infections, metabolic imbalances, or environmental toxins. IVF allows access to unique samples that help identify these processes and their impact on fertility. 1. Sample Collection \& Analysis * Diagnostic Cycle: Blood samples (early/late follicular phase), endometrial sample (7 days post-ovulation), and body composition analysis (BOD POD). * Oocyte Retrieval: Blood, follicular fluid, vaginal swab, and another body composition analysis (BOD POD). The male partner provides blood and an ejaculate sample. * After IVF: The culture medium where the fertilized egg grows is collected. Samples are analyzed for hormones, cytokines, metabolites, nucleic acids, proteins, and immune cells. Some granulosa cells are isolated and cultured. 2. Clinical \& Fertility Parameters The main outcome is a clinical pregnancy, but additional factors are examined: * Patient: IVF reason, AMH levels, pre-existing conditions, medications, smoking, pregnancy duration. * IVF parameters: Follicle counts, retrieved oocytes, fertilization method (IVF/ICSI), embryo quality, implantation rate, miscarriage rate, and live birth rate. * Newborn: Birth weight, length, sex. 3. Control Groups \& Data Management Control groups consist of couples where infertility is attributed to only one partner. All samples are pseudonymized before analysis to ensure data privacy.