Healthy period cycles

What is a period cycle

A period cycle (menstruation) is how your body gets ready for pregnancy.

During each cycle, your body releases hormones that help to:

• thicken the lining of your womb (uterus)
• release an egg from your ovaries
• shed the lining of your womb if you’re not pregnant.

You’ll have a period and bleed from your vagina when the lining leaves your body.

Who should have a period

Periods often start when you’re 12 or 13. It’s normal to get them earlier or later, but you should have them before you’re 16. They may not be regular at first but should become regular with time.

Periods usually stop in your 40s and 50s when hormone levels change (menopause).

You won’t get a period if you’re pregnant or use birth control or other medicines that stop your period. Some health conditions, hormone imbalances and lifestyle choices can also stop periods.

What to expect

Getting your period is different for everyone, but there’s usually a regular cycle. Knowing what’s normal can help you get the right health care if you need it.

Cycle length

The length of your cycle is the time between the first day of your period and the first day of your next period. It's usually between 21 and 35 days.

Read more about missed or absent periods.

Bleeding

The length of your period (how long you bleed for) is usually between 3 to 7 days. It's normal to lose 5 to 12 teaspoons (25 to 60 mL) of blood. You might notice more blood at the start, and less at the end of your period.

Period blood can be bright or dark red during heavy bleeding. It can also be pink, dark brown or black when your period is lighter. Seeing clots or clumps of tissue in your period is normal, but they shouldn’t be larger than a 50 cent piece (around 3 cm).

When periods first start they can be even heavier and last longer. This often happens if your ovaries haven't released an egg. Read more about heavy periods.

Period pain

Period pain can feel like a dull ache, cramps or strong pain in your lower abdomen. It can start before you see any blood, and last 2 to 3 days. It’s usually worse around 24 hours after you start bleeding. You can take paracetamol or ibuprofen, do gentle exercise or use a hot water bottle to help ease your pain.

Read more about painful periods.

Phases of your period cycle

Your body goes through 4 phases during a period cycle. Knowing what these are can help you track your periods and know when you’re likely to fall pregnant.

You get your period (menstrual phase)

Days 1 to 7

You shed the lining of your womb (endometrium), and blood flows out of your vagina. This can take 3 to 7 days.

Hormones involved: Low levels of oestrogen and progesterone.

Your eggs start to grow (follicular phase)

Days 1 to 13

Several eggs start to grow in small fluid filled sacs (follicles) in your ovaries. Usually, only one will mature. The lining of your womb also thickens with blood to get you ready for pregnancy.

Hormones involved: Follicle stimulating hormone (FSH), and an increase in oestrogen.

You release a mature egg (ovulation)

Around day 14

Your ovaries release the mature egg into your fallopian tubes. This is the easiest time to get pregnant. Your cervix will make clear, slippery mucus to help sperm swim up your vagina toward the egg. Your body temperature may rise, and you’ll absorb any immature eggs back into your body.

You might not release an egg very often in the first few years after your period starts.

Hormones involved: A sharp increase in luteinising hormone.

Your egg travels to your womb (luteal phase)

Days 15 to 28

Your egg moves down your fallopian tubes over 3 to 5 days. You’ll get pregnant if a fertilised egg attaches to the lining of your womb. If you aren’t pregnant, you’ll get your period again at the start of your next cycle.

Hormones involved: Progesterone and oestrogen will rise, then fall if you’re not pregnant. Human Chorionic Gonadotropin (hCG) also rises if you’re pregnant.

Managing your period

Your period shouldn’t stop you from living your daily life. It’s normal to feel some discomfort, but you should still be able to go to school, work, exercise, and do the things you enjoy. If your period is regularly stopping you from doing these things, talk to your GP.

There are different period products you can use to help manage your flow, including:

• period pads and liners
• tampons
• menstrual cups
• period undies.

If you’re getting your period for the first time, the Share the Dignity website has information to help you feel confident and prepared. healthdirect also has information about different period products.

Late periods

Sometimes periods don’t come on time. Your period is late if it comes more than 5 days after you’re due.

A late period could mean you’re pregnant, but you might also get late periods if you're:

• feeling stressed or have poor nutrition
• overweight, underweight, lost weight or do a lot of exercise
• using, or stopped using certain types of birth control
• nearing menopause.

Some medical conditions can also affect period cycles.

If you get a period more than 6 weeks after your last period, it’s a missed period.

Premenstrual symptoms

Premenstrual symptoms usually happen in the week before your period, when certain hormone levels rise and fall.

Common symptoms

PMS (premenstrual syndrome) is a group of mild symptoms that go away after your period comes, such as:

• headaches
• acne and tender breasts
• bloating, where there’s extra fluid on your body
• mood changes, or feeling tired, irritable or emotional.

They’re a normal part of your cycle.

Read more about periods on the healthdirect website.

Severe symptoms

PMDD (premenstrual dysphoric disorder) is a group of severe symptoms that affect your mood and can affect your daily life, such as:

• anxiety and panic attacks
• feeling angry, overwhelmed, tense or depressed
• thinking about suicide
• trouble sleeping or concentrating
• craving foods or binge eating.

These symptoms aren't normal. Talk to your GP for help and advice.

Read more about premenstrual syndrome on the healthdirect website.

When to get help

It isn’t normal for your period to stop you going to work or school or doing what you want in your daily life.

Talk to your GP professional if you have:

• abnormal bleeding or a coloured discharge between periods, or after sex
• severe premenstrual symptoms that affect your daily life
• signs that you may have PCOS (polycystic ovarian syndrome), endometriosis, or adenomyosis.

You should also talk to your GP if you have any of the following.

Painful or heavy periods if:

• your periods last more than 8 days
• you lose more than 12 teaspoons (60 mL) of blood during your period
• you need to change your pad or tampon every hour, for several hours
• you pass clots larger than a 50 cent piece
• you feel weak, dizzy, sweaty, short of breath or have chest pain or diarrhoea during your period.

Read more about painful periods.

Missing, late, irregular or absent periods if:

• your periods are less than 3 weeks apart, or more than 6 weeks apart
• your period often comes more than 5 days after you’re due
• your period stops for more than 6 months, and you’re not sure why
• you’re 16 and don’t have your period yet.

Read more about missing or absent periods.