Some people say they're 'allergic to their period.' Here's what to know about the autoimmune skin condition that causes it.

Mariia Vitkovska/Getty Images

Autoimmune progesterone dermatitis is a rare condition that can occur when progesterone rises during a woman's menstrual cycle. It can cause a physical reaction that may present differently depending on the person, but symptoms often mirror skin conditions like eczema, hives, or other allergic reactions.