What Puberty Is, and Why It Matters
Puberty: what it is, why it matters, and what published guidance actually asks of you.
Knowing what is typical helps families prepare, and puberty that starts very early or very late can signal a condition worth checking.
Key takeaways
- Typical start for girls: between ages 8 and 13
- Typical start for boys: between ages 9 and 14
- Most useful single change: Talk about body changes before they start, using correct names for body parts.
- Commonest mistake: Comparing a child's development to siblings or friends.
- See a doctor if any of the signs under "When to speak to a doctor" below apply to you.
The short answer
The years when the body develops into an adult body, driven by rising sex hormones.
Where it fits
This is part of Teen Health. Guidance sets out what to look for and what to do about it, which is what the rest of this page covers.
The numbers, in one place
| Measure | Figure |
|---|---|
| Typical start for girls | between ages 8 and 13 |
| Typical start for boys | between ages 9 and 14 |
| First period | usually about 2 to 3 years after breasts begin to develop |
| Early puberty | signs before age 8 in girls or age 9 in boys |
| Late puberty | no signs by age 13 in girls or 14 in boys |
What that means in practice
What to do with all of that:
- Talk about body changes before they start, using correct names for body parts
- Help teens prepare with period products, deodorant and a plan for school
- Expect growth spurts and bigger appetites, and offer nutritious meals and snacks
- Keep yearly checkups, where the doctor tracks growth and development
What gets people into trouble
And the things that tend to go wrong:
- Comparing a child's development to siblings or friends
- Teasing about voice changes, body shape or acne
- Ignoring signs that a teen is restricting food or exercising excessively to change body shape
Related topics
- Testosterone: What the Evidence Actually Says (Men's Health)
- Growth and Development: What the Evidence Actually Says (Children's Health)
- Acne: What Published Guidance Supports (Skin Health)
- Breast Cancer: Sorting the Evidence From the Noise (Cancer Awareness)
Where to go next
- Puberty: The Quick Reference
- Puberty: What Published Guidance Supports
- Puberty — the reference entry
- Teen Health: The Complete Guide
- HPV Vaccine: Sorting the Evidence From the Noise
- Teen Driving Safety: What the Evidence Actually Says
When to speak to a doctor
See your doctor if puberty starts before age 8 in girls or 9 in boys, there are no signs by 13 or 14, there is no period by age 15, or periods are very heavy or painful. Call 911 for severe sudden pain in the testicle or lower belly, or heavy bleeding with dizziness or fainting.
Where this comes from
- Eunice Kennedy Shriver National Institute of Child Health and Human Development — Puberty and Precocious Puberty
- MedlinePlus — Puberty
- American College of Obstetricians and Gynecologists — Your First Period
How this page was put together
Every figure, recommendation and warning above is taken from the guidance named in Where this comes from. Nothing on this page is inferred, summarized or generalized beyond what those bodies publish: where they give a number, it is their number, and where they are silent, so are we. Pages are rebuilt whenever the underlying record changes. Sign-off by a named clinician, where it has happened, is shown at the top of the page along with the date.
Medical disclaimer
This article is general information, not medical advice. It cannot account for your own history, medication or circumstances. Always speak to your doctor, pharmacist or another qualified health professional before making changes that affect your treatment, and never delay seeking medical advice because of something you have read here. In an emergency, call 911.
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