Periods, also known as menstruation, are a natural and normal part of the reproductive system where a girl, woman, or person bleeds from their vagina for a few days.

When you reach puberty, your body begins to produce hormones that trigger the menstrual cycle. During each cycle, the body goes through several hormonal changes where the uterus (womb) gets ready for a possible pregnancy.

It builds up a lining of tissue and blood to make the perfect place for a fertilized egg to attach to and grow. But if pregnancy doesn't happen, the uterus doesn't need that lining anymore, so it sheds it.

For most people periods will occur every 28 days or so, though some will experience their period more or less frequently.

The menstruation cycle


3 tablespoons

How much blood is normal for a period?

The shedding of the womb lining is what you will experience as blood and tissue flow from your vagina. This usually lasts around 3 – 7 days and is typically the equivalent of 3 tbsp of period blood, but it can vary from person to person.

When do periods start?

Most people will start getting their period during puberty around the age of 12.

Group of female friends

For some people this may be earlier or later, depending on when your body is ready. This is totally normal, though if you have not started your period by the age of 15 it might be a good idea to speak to your GP to investigate why.

Most people will stop getting their period when they are between the ages of 45 and 55 years old – this is called menopause.


Other symptoms you might have on your period

Most people will experience other symptoms before and during their period. This includes cramps and premenstrual symptoms (PMS) such as bloating, mood swings, breast tenderness, fatigue, and food cravings.

The symptoms you experience and their intensity will vary from person to person, and may also vary between your own periods.

What are cramps?

Cramps are caused by the contraction of the uterus to help the period blood flow out of the vagina. They usually feel like throbbing pains in your lower belly, and can be really uncomfortable and painful. Most people will find that their cramps are worst during the first few days of their period, when the period flow is heaviest.


How to alleviate the symptoms of cramps.

  • Place a heated pad or hot water bottle on your stomach, lower back or lower abdomen
  • Take a warm bath or shower
  • Resting
  • Take paracetamol
  • Lightly massage your lower abdomen
  • Do some light exercise
  • Having an orgasm (masturbating by yourself or with a partner)
  • Take birth control, such as the pill, implant or IUD.

You can discuss this with your GP.


When to ask your GP

Although cramps are a pretty normal part of getting your period, sometimes people have period cramps which are so painful that they find it hard to do everyday things like go to school or work.

If you have severe period pain or your normal pattern of period changes, you should see your GP to check if the pain is being caused by a more severe condition and help determine the best treatment.

Painful period cramps might also be a sign of conditions such as:

  • Endometriosis – a condition where cells similar to those lining the uterus grow elsewhere in the body causing inflamation. It affects around 4.5% of UK women.
  • Pelvic inflammatory disease – an infection in your reproductive organs.
  • Adenomyosis – when the tissue that lines your uterus grows into the muscle wall of your uterus.
  • Uterine fibroids – non-cancerous tumours which grow inside, in the walls of or on the outside of your uterus.

Understanding Premenstrual symptoms (PMS)

Before and during your period, you may also experience a range of physical and/or emotional symptoms. These are called premenstrual symptoms, or PMS, and are caused by the hormonal changes that your body experiences during your menstrual cycle. Some people will experience PMS symptoms every time they have a period, whereas others will only get it occasionally and some might not get them at all.

There are two main kinds of PMS symptoms:

Physical symptoms, including:

  • Craving certain foods or being more hungry than usual
  • Tender, swollen or sore breasts
  • Feeling bloated
  • Gaining a little weight
  • Headaches
  • Dizziness
  • Swelling in your hands or feet
  • Feeling more tired than usual
  • Skin problems

Emotional symptoms, including

  • Feeling sad, depressed, tense or anxious
  • Mood swings
  • Feeling more irritable or angry
  • Crying suddenly
  • Not feeling very social
  • Having trouble concentrating
  • Having trouble falling asleep or staying awake
  • Changes in your desire to have sex

Getting help and guidance with your period

Periods are not something to be ashamed of or embarrassed about. They are a natural and healthy part of a woman's life.

If you have any concerns or questions about periods, it's always a good idea to talk to a trusted adult, like a parent, family member or a healthcare professional. They can provide guidance, support, and any additional information you may need.


Do trans guys get periods?

Not everybody who gets a period identifies as a girl or woman; transgender men and genderqueer people who have uteruses, vaginas, fallopian tubes and ovaries also get periods.

Although everyone’s experience is unique and there is no ‘right’ way to feel, having a period can be a stressful period for some trans people because it is a reminder that their body does not match their true identity. This discomfort and anxiety is sometimes called gender dysphoria.


If you experience gender dysphoria when you get your period, you are not alone. It may be helpful to access support.

Spectra run a variety of peer-led services for all trans and gender-diverse peers, including counselling, peer mentoring, 1-2-1 mentoring, advocacy, and social groups.