<p>In recent years, menstrual blood has emerged as a promising non-invasive biological specimen for the diagnosis of female genital tract disorders because it provides rich molecular information while avoiding several limitations associated with conventional diagnostic approaches. Traditional diagnostic methods often rely on invasive procedures, which may impose physical discomfort and psychological distress on patients and limit the feasibility of repeated sampling and large-scale population screening. In contrast, menstrual blood collection is non-invasive, readily repeatable, suitable for self-collection, and associated with high patient acceptability, making it particularly well suited for longitudinal monitoring and large-scale screening programs. This review systematically summarizes recent advances in the application of menstrual blood for the diagnosis of major female genital tract diseases, including lower genital tract infections, endometriosis, endometrial carcinoma, and cervical cancer. The diagnostic utility and current level of clinical evidence for different molecular biomarkers are critically compared. In addition, key pre-analytical and analytical factors affecting assay performance are discussed, including sample collection protocols, timing and handling procedures, and detection methodologies. This review also addresses major translational challenges, including the lack of standardized collection and processing protocols, insufficient prospective clinical validation, and unresolved issues regarding applicability across diverse populations. Overall, menstrual blood represents a novel liquid biopsy specimen with considerable potential for the early detection and risk stratification of female genital tract diseases. However, successful clinical translation will require large multicenter prospective studies and the establishment of harmonized technical and regulatory standards.</p>