Understanding Periods
HOT TAKE: Periods aren’t just a “girls’ thing”. They’re a normal and healthy feature of human physiology. When boys understand the menstrual cycle, too, everyone wins! It dispels myths, reduces teasing, builds respect, and makes it easier to talk about health, healthy relationships, and pregnancy. Learning about periods means being informed, supportive, and confident about how all bodies grow and change.
Menstrual Cycle/Periods
Most girls get their first period between 9 and 15 years old. Everyone’s body is different, so there’s no exact “right” time. A period happens because the body is preparing for the possibility of pregnancy. Each month, the tissue that lines the inside of the uterus builds up to cushion a possible pregnancy. If pregnancy does not happen, the lining leaves the body as blood through the vagina—that’s the period. It’s a normal, healthy sign that the body is growing and working the way it should.
Counting the Menstrual Cycle
The menstrual cycle is the amount of time from one period to the next, not the number of days you bleed. The cycle starts on the first day of bleeding, that’s day 1. Keep counting each day after until your next period starts. The day before the next period begins is the last day of that cycle. For example, if the period starts on September 1st and the next one starts on September 29, then the cycle is 28 days long.
Everyone’s cycle is a little different, and for teens it can be irregular at first—so patients should not worry if it doesn't come on the same day every month. But if patients experience symptoms that don’t feel right (very painful cramps, mood swings, worsening acne, skipping many months in a row) then they should follow up with a trusted medical provider.
An Important Note About Period Trackers
It can be tempting to download a period tracker app but many public health professionals urge patients to keep their personal data off of period trackers to prevent private organizations from having access to private patient data.
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Article: Risks of Period Tracking Apps
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Should a patient wish to use a period tracker app, TBF recommends downloading one that stores patient data locally (on your own device) rather than sending it to the cloud. These include Menstrudel, Nelya, and LocalOne.
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