What The Age Of Your First Period Reveals About You

Welcome to womanhood.

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I know exactly how old I was when I got my first period.

I was in 6th grade, so I was 11. I don't remember much about the first glimpse of scarlet in my underwear. I'm sure I was upset, frightened, and alarmed. So, you can imagine how unhappy I was when I read this article

The age you are when you first start menstruating, also known as menarche, has a sizable influence on many factors in your life.


RELATED: You'll Live Longer If You Got Your Period At This Age

But what's most concerning is that women who got their period before age 12 are at a higher risk for health issues like both heart disease and breast cancer. Thanks, Aunt Flo!

Researchers from the University of Oxford spent over a decade studying how the menstrual cycle affects a woman's overall health. And, in 2012, they published their findings in the journal Circulation

The researchers reanalyzed original data from 117 studies worldwide, including almost 120,000 women with breast cancer, and over 300,000 women without the disease.


They discovered that starting periods earlier had a greater impact on breast cancer risk than finishing periods later did, suggesting that the effects of these factors may not simply reflect the number of reproductive cycles in a woman's lifetime.

"The size of our study, the wide range of ages considered, and the vascular diseases being examined made it unique and informative," the study's lead author Dr. Dexter Canoy said in 2014

"Childhood obesity, widespread in many industrialized countries, is linked particularly to the early age at which the first menstrual cycle occurs. The research team consistently found throughout the study that those who were healthy and lean had a first menstruation age closer to 13 than those who were overweight or obese."

Dr. Gillian Reeves of the Cancer Epidemiology Unit at the University of Oxford, and a lead researcher on the study, added, "Our new research should help us towards a better understanding of the way in which female sex hormones affect breast cancer risk. 


We already knew that hormones associated with reproduction have a big impact on breast cancer risk, and that starting periods early and having a late menopause increase risk. But these findings suggest that sex hormone levels may be more relevant for specific types of breast cancer — ER-positive tumors, and lobular, rather than ductal tumors."

The head of health information at Cancer Research UK, Hazel Nunn, stated, "Even though women can't control the age they start their period, there are many things they can do to reduce their breast cancer risk. Keeping a healthy weight, cutting back on alcohol, and having a more active lifestyle will all help to prevent the disease developing."

RELATED: Period Flu? What It Really Means If You Have Flu-Like Symptoms Before Your Period

Researchers also found that the later a woman finishes having periods (one year without periods and you're in menopause), the more at risk she is for developing breast cancer.


The research showed that the more exposure to hormones, the more likely your body will develop breast cancer.

The Susan G. Komen Breast Cancer Foundation's research had similar findings. They found that the risk of getting breast cancer rose 15-20 percent for women who began their periods before the age of 11 than for women who started getting their periods at 15 or older.  

Their research explained that it also has to do with how much estrogen a woman has been exposed to and that the age a girl starts her period can also be impacted by her lifestyle and how healthy it is.


When you're a young girl getting your period for the first time, the idea that your own body chemistry is now putting you at risk for things like heart disease and breast cancer is the last thing that enters your mind.

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Christine Schoenwald is a writer and performer. She's had articles in The Los Angeles Times, Salon, and Woman's Day. Visit her website or and her Instagram.