system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What happens when females with hemophilia go through their menstrual cycle?

No this isn't a set up for a joke, I am genuinely curious.
gpt
That's not really blood, not all of it. It's the lining of the *endometrium*, the outer layer of the uterus that holds the egg after fertilization. If there's no fertilized egg, the body discards that tissue.