tamponIt can say a lot about your health.iStock

Did you know that the term for your first period is "menarche"? It's pretty catchy, particularly as opposed to "a seriously stressful event that likely involves at least one panic attack and/or mystification about tampons". (I did NOT know how to put the damn thing in.) Menarche — pronounced MEN-ar-kee — is likely a distant memory for you if you're in your mid-20s now. But science tells us that the age at which you first got your period (or visit from Aunt Flo, monthly gift, Eve's curse, whatever) can be an indicator of many things about your life, nutrition, and even future health.

Menarche has been significant in many cultures for centuries. It's a pretty major event — it signifies a girl "becoming a woman," or entering puberty and her child-bearing years. Medical Daily reports that communities in several countries, including Sri Lanka and Ghana, have lavish menarche ceremoniesto celebrate the occasion. More bizarrely, Ritualwell, which records Jewish rituals across cultures, reports that some Orthodox Jewish women will be slapped across the face by their mothers when their first period happens. (It's supposed to be in the hope that the slap will be the worst pain you ever experience as a woman, apparently.)

But it turns out that the specifics of your menarche may say more than you realize. First period age is influenced by a huge amount of factors, including up to 100 genes in your body. The average age of first period in the Western world has been getting lower, from an average of 17 over a century ago to around 13 today. That may be partially due to better nutrition, which means that we weigh more at a younger age, and thus our bodies can cope with childbearing earlier. But researchers are still arguing over whether it might also be due to genetic changes, more hormones in our food, or other environmental factors. Either way, it seems that your first period can be a big factor in your life. So what does it mean?

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