The context of what Kathleen said about trans people and periods.
Some people now apparently believe that trans women can be biologically female, because they take hormones. In fact, being biologically female involves having XX chromosomes, and some or all of a set of primary sex characteristics. There are complications with people who are born intersex, but that is of no relevance to the person who is born a biological male and then who later starts taking hormones. If academics don’t start saying this more loudly, the public will get more and more confused. We will lose a powerful explanation of the sex-based oppression of females; we will also lose the capacity to talk about female health and reproduction, and much else besides. I saw something on social media the other day that said that trans women could get periods. And it had over 1000 likes.