Menarche is a girl’s first menstrual period, signaling that she’s starting ovulation and that pregnancy is now possible.  Girls can now say that they have cramps and they need to stay home, but of course I would never do that.  Weight plays a role in terms of when girls get their first period.  Female athletes like gymnasts or runners who have low body fat, may start menstruating later or may skip periods.  It has to do with the body fat percentage, a certain amount is healthy and necessary to be able to get pregnant and have a child.  If female athletes train really hard and limit their calories, or girls who are anorexic, their bodies may have fewer periods because of the low body fat percentage.  Childhood obesity is connected with the release of the hormone leptin that’s related to the start of menstruation, so girls who are overweight tend to get their periods sooner (Berger, 2018; Feldman, 2014).


In the past 100 years, girls in the United States and in other cultures have been going through puberty at earlier ages.  In 1860, the average age of puberty was 17 years old, now it’s 12, decreasing by 5 years (Feldman, 2014; Hernandez, 2018).  For information on very early puberty see the article on precocious puberty.


Berger, K. S. (2018). The developing person: Through Childhood and adolescence (11th

ed.). New York, NY: Worth.  

Feldman, R. S. (2014). Child development: A topical approach. Boston, MA: Pearson. 

Hernandez, D. (2018). The decreasing age of puberty. Retrieved from