Key points about puberty

  • Puberty is the process of becoming an adult and is caused by hormones produced in the body. Girls and boys experience different changes in their bodies during puberty.
  • The usual age of puberty is between 10 to 14 for girls and 12 to 16 for boys, but don't worry if your child's puberty falls outside this age range.
  • Your child's body will be undergoing a lot of changes that affect them physically and emotionally.
  • This stage can be difficult for both the young person and their parents.
  • Talk to your doctor if you or your child is having any difficulties with this developmental stage.
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Puberty usually starts between the age of 10 and 14 for girls and the age of 12 and 16 for boys.

There are three types of puberty:

  • normal puberty, which happens between the ages of 10–14 for girls and 12–16 for boys
  • precocious puberty or early puberty, which happens before age 8 in girls and before age 9 in boys
  • delayed puberty, which happens after the normal age range for puberty. See a doctor if you are concerned your child has delayed puberty.

If your child seems to be starting puberty much earlier or later than their peers and you are concerned talk to your doctor.

Physical changes in girls

  • The first sign of puberty is usually breast development. It is normal to feel breast tenderness sometimes during the process.
  • Then hair grows in the pubic area and armpits.
  • Breasts continue to grow, hair in the pubic area becomes coarser, white vaginal discharge occurs and acne arrives.
  • Girls also grow taller.
  • After around 2 years, girls have their first menstruation (period). Menstruation usually happens last. Read more about menstruation.

Video: Am I Normal (Girls and Puberty)

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(Kidshealth, USA, 2014)

Physical changes in boys

  • Puberty usually begins with the testicles and penis getting bigger.
  • Then hair grows in the pubic area and armpits.
  • Muscles grow, the voice deepens, facial hair develops and breasts may temporarily swell slightly as puberty continues.
  • They may get wet dreams (ejaculation while asleep) and start to sweat more.
  • Acne often develops. Read more about acne.

Video: What Boys Want to Know About Puberty

This video may take a few moments to load.

(Kidshealth, USA, 2015)

Mood changes in boys and girls

The increase in female and male hormones can be a difficult time for young people as they cope with changes brought about by puberty. Feeling self-conscious, mood swings and intense emotions are all par for the course during puberty.

It’s also a time for your child to forge their identity, and they’ll want to feel accepted by their peers and be 'cool'. They may face issues to do with their sexuality, gender identity and mental health. Some people also choose to drink alcohol or take drugs when they are feeling stressed. Read more about alcohol and mental health.

Puberty can be a challenging and tumultuous time not just for young people, but also for parents. Check out our Support for Parents section below.

Physical changes

Puberty is a normal part of life. Puberty is the process of becoming an adult and is caused by hormones produced in your body. 

Allow yourself time to adjust to what you are experiencing and try to get support from others, especially from your family. If they understand what you are going through it will help them know how they can best support you.

For girls, during puberty your body starts preparing every month for a baby. Your ovaries start releasing eggs and your body starts to make the female hormones oestrogen and progestogen. These hormones are responsible for physical changes such as breast development, hair growth in your pubic area and armpit, height spurt, vaginal discharge and acne. After about 2 years, your periods start.  

For boys, your body starts producing the hormone testosterone. This leads to your testicles and penis growing, hair growth around your testicles and penis and facial hair developing. Your shoulders and chest will broaden and you may notice a slight temporary swelling in your breast area. Eventually, your voice becomes lower and you start growing taller. You may get wet dreams (ejaculations when asleep) and start to sweat more. The increase in testosterone also stimulates the production of sperm.

Mental health

Due to the hormonal and physical changes that happen in your body during puberty, you may feel more emotional. You may notice changes in your thinking and care more about what others think. Looking after yourself can help you feel better. This includes keeping active and eating a healthy balanced diet. Read more about healthy living topics for teenagers.

An increase in sexual feelings is normal as part of puberty. You may be more curious about sex. It is important to understand what sex is and when sex is appropriate. Safer sex is also important to avoid diseases and unwanted pregnancy. Read more about sex(external link), safer sex(external link) and contraception.

Puberty can also be a stressful time as you may also have to make life decisions while coping with the changes brought about by puberty. Some stress is good for you and helps you to perform at your best. But when you are under too much stress for too long, your performance decreases and your overall health and wellbeing is affected. Read more about stress. For some people, this may lead to anxiety and depression.  

Some people choose to drink alcohol or take drugs when they are feeling stressed. Alcohol and drugs may feel as though they improve your mood, but the price for a temporary boost to your feelings is usually a longer period of low mood and an increased risk to your mental health over time. Read more about alcohol and mental health, and find out about how much a standard drink is, the effects of alcohol on your body and where to get help if your drinking is becoming a problem here.

Support for those going through puberty

The Lowdown(external link) This website has been created to help young people understand and deal with depression. FREE text 5626 or chat online(external link)
SPARX(external link) Helps young people learn skills to deal with feeling down, depressed or stressed.
What’s Up(external link) This is a safe place for children and young people to about anything at all. FREE call 0800 WHATS UP (0800 942 8787) from any NZ phone or chat online(external link)


The following numbers are free to call from a New Zealand landline:

Free call or text 1737(external link) any time, 24 hours a day
Youthline(external link) (0800 376 633)
Free helplines 24/7 – free TXT 234, free call 0800 37 66 33, chat online(external link) (10am – 10pm) or email.  Youthline provides access to support and help for young people, as well as youth development and leadership programmes. They also offer a counselling service(external link) with up to 8 free counselling sessions (over the phone, face-to-face or via video call), in Auckland.
Kidsline(external link) 0800 543 754 (4pm–9pm weekdays)
Depression line(external link) 0800 111 757 (24 hours, 7 days)
Lifeline(external link)  24 hour telephone counselling 0800 543 354 or 09 522 2999 (within Auckland) 
What’s Up(external link) 0800 WHATS UP (0800 942 8787) Phone counselling is available Monday to Sunday, 11am-11pm. Online chat is available Monday to Sunday 11am-10.30pm. Free to call from both New Zealand landlines and mobile phones.
Samaritans(external link) 0800 726 666 (24 hours, 7 days)

Support for parents

Relationships and sexuality education(external link) Sexual Wellbeing Aotearoa
Parenting teens – the teenage brain(external link) KidsHealth NZ
How to talk about puberty (boys)(external link) The Parenting Place NZ
How to talk about puberty (girls)(external link) The Parenting Place NZ
Surviving adolescence – for parents and carers(external link) Royal College of Psychiatrists, UK

The following links provide further information about puberty. Be aware that websites from other countries may have information that differs from New Zealand recommendations.   

Changes at puberty(external link) Sexual Wellbeing Aotearoa
Your body(external link) Sexual Wellbeing Aotearoa
What's happening to my body? Stages of puberty in girls(external link)
Stages of puberty in boys(external link)
Positive puberty – year 6–8 sexuality education(external link) TKI, Ministry of Education, NZ
Puberty information for parents and kids(external link) Child Development Institute, US
What happens during the stages of puberty?(external link) innerbody, US, 2022  
Growth and puberty(external link) Youthline NZ
Puberty signs(external link)
Stages of puberty(external link) NHS, UK
All about growing up(external link) Sexual Wellbeing Aotearoa, NZ, 2019



  1. Puberty(external link) Medline Plus
  2. Stages of puberty(external link) NHS, UK

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Credits: Healthify editorial team. Healthify is brought to you by Health Navigator Charitable Trust.

Reviewed by: Dr Sharon Leitch, GP and Senior Lecturer, University of Otago

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