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How do periods change over time?
Periods don’t stay the same throughout your life. You may experience a range of changes depending on your age, your health and other lifestyle factors. Sometimes it can be hard to know if what you’re going through is normal or not. Here I’ll explore what you can expect from puberty to perimenopause and beyond.
Hi, I'm Dr. Samantha Wild. I'm a GP of over 20 years and I'm the Women's Health clinical Lead for Bupa Clinics. I'm passionate about shifting the stigma surrounding many female health related topics and empowering women to see correct information and get the support that they require.
What age do most people start their periods?
The average age for periods to start is age 12. But most people start their periods between the age of ten and 15. Everybody's different. Some will start earlier. Some start later.
Why do some people start their period later than others?
Most people start their periods between the age of ten and 15, but for some, puberty may start a little earlier or a little later. Periods usually start around two years after puberty has started.
This can be determined by genetic and environmental factors. For example, black girls are more likely to start their periods earlier than white girls.
Your periods may start later, If you you're under weight loss of exercise, suffer with particular illnesses or you take certain medications.
It is also possible for a girl to get pregnant before her period has first started. However, if you haven't started a period by the age of 16, or if there are no known signs of puberty by the age of 14, we do recommend that you see a GP.
How many periods does an average woman have in her lifetime?
The average number of periods that a woman has throughout her lifetime is said to be 450. But it is obviously also determined by a number of factors.
It will be affected by when she first started her periods. How long a cycle her cycle is. Most women will have between nine and 12 periods a year. When she meets the menopause, how many pregnancies she's had and whether she's breastfed her children.
It will also depend on whether she suffered with certain illnesses and what medication she has taken.
What can disrupt periods over a woman's lifetime?
There are lots of things that can disrupt a woman's menstrual cycle, and these can be divided into lifestyle factors and medical factors.
Lifestyle factors include stress, gaining or losing significant amounts of weight, or extreme exercise. Women that have a lower body fat may find that their periods stop.
Certain health conditions are associated with missing periods. Pregnancy, different hormonal contraception can disrupt the cycle, and it can take a while for the cycle to return after the hormonal contraception is stopped. And breastfeeding will also stop the cycle.
Viruses and other illnesses, such as thyroid disease, can also affect the regularity of the cycle, as can different medications.
Viruses in other illnesses, such as thyroid disease, can also affect the way that the body functions. And different medications such as antipsychotics, steroids and anticoagulants can also affect the period too.
Some women may also experience changes to their periods in the perimenopause. The lead up to the menopause, where their periods may stop, get more frequent, get heavier or get lighter.
Different gynaecological conditions may also affect the menstrual cycle. Polycystic ovarian syndrome, Endometriosis, Gynaecological cancers and pelvic inflammatory disease may all affect the periods, but the treatment of them may also affect the cycle too.
When do periods go back to normal after pregnancy?
So women may start having periods as early as 4 to 6 weeks after delivery. We advise a contraception is used from three weeks after delivery as ovulation may occur then.
Some women may find that it takes longer for their periods to return though, particularly if they are fully breastfeeding or if they have commenced contraception at the time of delivery.
Why do periods change with the perimenopause?
Perimenopause is the lead up to the menopause when hormones start to fluctuate before they decline for good. this can cause a wide range of physical and mental symptoms.
The changes in hormones can lead to longer cycles because a woman is not ovulating each month, but can also lead to shorter cycles with more frequent periods and could cause heavier or lighter bleeding.
Although changes in the frequency and duration of periods and the amount of blood loss can be normal throughout the perimenopause. There can be times when other medical conditions should be suspected.
If a woman has a significant amount of bleeding, or bleeding in between her periods or after intercourse, or is experiencing a lot of pain, we do recommend that she consult with a doctor.
When does the average woman enter the menopause?
The average age of the menopause in the UK is age 51. The majority of women will go through the menopause between the ages of 45 and 65.
One in 20 will go through the menopause between the age of 40 and 45, one in 100, under the ages of 40 and and one in 1000, under the ages of 30.
If you go through the menopause under the age of 40, this is said to be premature menopause. You've said to have reached the menopause when you haven't had a period for a year.
Often when people talk about going through the menopause, they're actually talking about the time of the perimenopause. This is a time when your hormones start to fluctuate, but before they decline for good and before your periods stop completely. At this time, though, you may suffer with other physical and mental symptoms. Your periods may become lighter or heavier and may become further apart or more frequent. This period in your life may last for on average four years, but for some it can be a decade or more.
What age do most people start their periods?
Most people start their periods between the ages of 10 and 15. The average age is 12. Throughout your lifetime you will have around 450 periods in total. But this depends on:
- how early you start menstruation
- how many (if any) pregnancies you have
- when you enter the menopause
- how long your cycle usually is
Why do some people start their period later than others?
Your body will start having periods when it’s ready to. This is usually a couple of years after you have started puberty, but this is influenced by both genetic and environmental factors. If you’re underweight, have chronic illnesses, or are very stressed you might experience a delay in starting your periods.
When you start your periods can depend on your ethnicity too. Some studies show that black girls are likely to start their periods earlier than white girls. If you have not started your periods by the age of 16 then it’s a good idea to see a doctor for a check-up.
What can disrupt your periods?
Many different things can cause changes to your periods. These can include lifestyle factors such as gaining or losing lots of weight, and extreme exercise regimes such as long distance running or gymnastics.
Your periods can also change because of certain health conditions. These can include thyroid conditions and bleeding disorders. You might also experience period disruptions if you take medications such as steroids too. Birth control pills can also lead to period disruptions, even after you’ve finished taking them.
There are also several gynaecological conditions which can affect your periods. These include endometriosis, polycystic ovary syndrome and pelvic inflammatory disease, as well as certain cancers.
When do periods go back to normal after pregnancy?
You might start having periods as soon as four weeks after giving birth. This is why birth control is recommended at three weeks post birth due to the chance of ovulation (which could lead to pregnancy if you have unprotected sex at this time).
Whether or not you breastfeed fully can also affect how soon your menstrual cycle begins again, and some people will be offered birth control beginning straight after birth.
How do periods change during the perimenopause?
The perimenopause is a time of hormonal changes. Your hormone levels will rise and fall before the ultimate decline of oestrogen at the end of the menopause. It’s the hormonal changes that causes a range of physical and mental symptoms during the perimenopause.
Such changes can lead you to have longer or shorter menstrual cycles. They may also affect how heavy your periods are too. If you notice bleeding between your periods, very heavy, painful periods, or bleeding after sex, see a doctor to check everything is normal.
When do most people enter the menopause?
In the UK, the average age of reaching the menopause is 51. But this can vary and is usually somewhere between the ages of 45 to 55. If you enter menopause before the age of 40 it’s considered a premature or early menopause.
You are said to have reached the menopause when you’ve not had a period for at least 12 months. But the symptoms of perimenopause can last for up to 10 years. For many people though they tend to last between 12 months and four years.
If you have heavy, painful, or irregular periods, you’ll know just how disruptive they can be, both physically and mentally. With our Period Plan, you don’t have to face these problems alone.
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