Women with a history of certain autoimmune disorders are significantly more likely to have primary ovarian insufficiency, and vice versa, according to a new study. Periods affect different people in different ways, but they affect about half the world’s population directly. Whether it’s for demystifying conditions like premenstrual dysphoric disorder, or helping people know what period symptoms could be warning signs, periods are worth talking openly and learning about. Scientists just took our collective understanding of them one step further, by finding an association between autoimmune dise…