Also TMI (and let's be honest: mega-creepy) I can tell when women are menstruating with about 90%+ accuracy if we share small-ish indoor space for a few minutes

Also TMI (and let's be honest: mega-creepy) I can tell when women are menstruating with about 90%+ accuracy if we share small-ish indoor space for a few minutes. (As confirmed by female family members.) It's not so much an obvious smell as a perceived "sharpness" that feels related to the sense-modality of smell, but is not exactly equivalent to it. I wonder sometimes if it's a pheromone-based phenomenon.