Girls usually start going through puberty between the ages of 8 and 14, with the average age being around 11.
During this time a girl will experience a lot of physical and emotional changes caused by the female sex hormones oestrogen and progesterone:
1. Body changes
Lots of changes occur over the course of puberty, and happen at different times and rates for everybody.
You will notice that:
- You will get taller.
- Your hips will get bigger.
- You will start to develop breasts.
- Your periods will start.
- You will begin to grow hair on your legs, your genitals and in your armpits. Some girls prefer to shave or wax the hair under their arms and on their legs, but it is up to you whether you do this or not.
2. First periods
One of the biggest changes for girls is starting having periods (also called menstruation), which is where you bleed from your vagina each month. Having periods shows that your body is able have a baby.
The average age for getting your first period is 12.
The time from the first day of your period to the day before you next period is called your ‘menstrual cycle’.
Your cycle could last from 24-35 days, a 28-day cycle is the average length.
This is what happens during your menstrual cycle each month:
- The sex hormone oestrogen causes your ovaries to develop an egg.
- The egg is released from one of your ovaries (called ‘ovulation’).
- The egg travels down your fallopian tubes.
- If you have had sex without a condom, the egg may be fertilised by a sperm, meaning you could become pregnant.
- At this time the hormone progesterone thickens your womb lining in preparation for pregnancy.
- If a pregnancy occurs, the fertilised egg implants into the womb lining. (Your body will absorb the egg if it isn’t fertilised.)
- If there is no pregnancy, the lining of the womb comes away and you have your period (where you bleed from your vagina).
- Your period will last for around three to seven days.
It is completely normal and natural, and you can use sanitary towels, tampons or menstrual cups to soak up the blood. You will probably find towels easier to use to start with, tampons can take a bit of getting used to.
At first your periods may not be very regular, but they usually settle down.
Lots of girls feel a bit uncomfortable when their period comes as it can cause abdominal cramps, known as period pain. You might also get pains in your back or thighs. If you get these you may find a hot water bottle and a painkiller helps!
NHS Choices have a video showing the menstrual cycle.
3. Vaginal discharge
As well as periods, the menstrual cycle also causes the vagina to make a clear or milky discharge that might change slightly day to day.
This is completely normal and helps to keep the vagina healthy and clean.
If you notice any sudden changes to your discharge or it becomes strong in smell or colour, this may be the sign of an infection. If this happens, or if you are unsure whether your discharge is normal, your GP or nurse will be able to advise you.
4. Spots or acne
Most teenagers experience getting spots on their face, and unfortunately some people get more than others. These are caused by hormones and have nothing to do with eating chips and chocolate! Acne is where you have painful spots and bumps on your skin.
What to do if you have acne:
- Use a mild cleanser and an oil-free moisturiser.
- If you have a mild case of acne you can buy an over-the-counter treatment from your local pharmacy.
- If your acne is more severe your GP may prescribe a treatment.
You will also find that your sweat changes meaning that you sweat more than you did before and that it is smellier - this may cause body odour (BO).
There are lots of antiperspirants and deodorants available. Deodorants are fragranced so they mask the smell, whereas antiperspirants reduce the amount of sweat you produce. Regular baths and showers will also help.
6. Sexual feelings
All the extra hormones in your body affect your mind as well, and you may find that you are becoming more interested in sex, start fancying people and think about having a boyfriend or girlfriend.
You may also be interested in exploring your own body and what feels good through masturbating, which is completely normal.
All this is part of your developing sexuality.
Unfortunately, not all your new feelings will be exciting sexual ones. You might also find you become moodier, have more arguments with your family and friends or feel more confused and worried about things than you used to because lots of things are changing.
It's normal to feel like this and if you are worried it might help to talk things through with someone you trust.
Some girls and women find they feel irritable and moody in the two weeks before their period arrives. This is called either premenstrual syndrome (PMS) or premenstrual tension (PMT) and it usually goes away again when your period starts. PMT often goes hand in hand with physical symptoms like tender breasts and bloating. Healthy eating, managing stress, exercise and getting enough sleep can help to manage PMS, but if you find it is affecting your life speak to your GP as they may be able to help.
These emotional ups and down are normal during puberty, and most women will experience PMS at some point.
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