'It's a very unique biological specimen': The scientists using menstrual blood to diagnose diseases - BBC

Researchers are exploring menstrual blood as a non-invasive diagnostic sample that can reveal conditions from endometriosis and cervical cancer to diabetes, vitamin D deficiency and pollutant exposure. Because diagnoses for some conditions (like endometriosis) often take years and require invasive procedures, menstrual-blood tests could offer earlier, easier detection and monitoring. The recent renaming of PCOS highlights a broader effort to improve how reproductive conditions are defined and diagnosed, suggesting menstrual-blood diagnostics could play a role in translating clearer disease definitions into less invasive clinical tests.