Before you look at the chart below, repeat after me: “Normal is a range. Being outside the range doesn’t mean there’s a problem—but I should see a doctor.”
Bleeding lasts 1 to 7 days.
Bleeding lasts longer than 7 days.
Cycles (the time between Day 1 of one period and Day 1 of the next) last about 21 to 40 days. The middle range is 28...
Boys usually begin puberty between the ages of 10 and 15. That's two years later than most girls.
Starting at about age 12 or 13, and as early as 9, hormones called androgens bring on a number of physical changes, says Lori Legano, MD, assistant professor of pediatrics at New York University and attending physician for the adolescent clinic at New York's Bellevue Hospital Center.
One of the first things guys start to notice is that their testicles and scrotum (the sac located underneath the penis) start to get larger. Their penis gets longer and wider and pubic hair begins to grow in, too.
Legano says male hormones are the reason for a number of other changes. Maybe you’ve noticed some of these developments in the boys you know:
Hair has started to grow on their faces.
Hair under the arms starts to show up.
Body odor becomes an issue.
Guys and girls have different timelines when it comes to puberty.
It breaks down like this:
Girls grow very fast (this could start as young as age 8), get their periods, their growth plates fuse, and they stop growing. Puberty over.
Boys, on the other hand, take their sweet time. They may not have a major growth spurt until age 15 or 16, and they sometimes keep growing into their early 20s.
That’s why around the 8th grade you have taller girls and smaller boys.
“Boys are slow to grow but then they catch up later,” Legano says.
Puberty is the fastest you’ll grow, other than when you’re a little baby, says Marc Lerner, MD, of the University of California, Irvine.
All that change can be awkward at times.
“Guys are also sometimes uncomfortable with how their body is changing in terms of height, their physical strength, or acne,” Lerner says. And, guys who develop slower and are smaller than other boys may feel really stressed about it.
On top of that, boys’ voices become deeper and may start to crack. Guys can blame their growing larynx, or voice box, for that.
If a boy seems pretty shy about talking to you or speaking up in class at this age, it could be that he feels awkward about his voice.
Cut him some slack -- wouldn’t you clam up if you were worried about your voice failing you in public?