How a woman's period changes throughout her life

What happens to your periods as you age? [Photo: Getty]
What happens to your periods as you age? [Photo: Getty]

Sure we know that as we get older our bodies change (hello wrinkles and everything heading south) but did you realise that ageing can have an impact on our periods too?

The menstrual cycle and our periods are actually dictated by hormones. The levels of those hormones in our bodies alter during different stages of our lives, so it makes sense that our periods change, too.

While there’s no real ‘normal’ when it comes to periods, as each woman is different, there are some typically accepted characteristics of a healthy visit from Aunt Flo.

“When it comes to menstrual cycles, women can have quite a lot of variation,” explains Mr Narendra Pisal, consultant gynaecologist at

“The normal gap between the first day of two consecutive cycles (also known as cycle length) can range between 21 and 42 days. Having said that, many women have regular cycles like clockwork and can often predict their next period accurately to the day.”

According to Mr Ian Currie, consultant gynaecologist at BMI The Chiltern Hospital, Buckinghamshire average blood loss for a period is around 10 to 35mls.

“Typically, a period will last 3-5 days but there is great variation,” he says. “Cycle length also varies and having a slightly shorter and longer cycle does not necessarily mean there is anything wrong.

“Periods can change for lots of reasons,” Ian Currie continues. “For example, Polycystic Ovarian Syndrome can make the cycle much longer and the periods lighter or even non-existent. Whereas, uterine fibroids can cause periods to be extremely heavy.”

And even though there is a lot of variation between women, we’ll also find our period length, flow and cycle will change over time.

“There are many factors that affect periods as we age from body mass index, contraception, pregnancies, breastfeeding and menopause,” explains Mr Pisal. “All these can have a significant impact on the hormone balance which then can cause period changes.”

So just how can we expect our period to change as the years roll by?


According to Ian Currie, most girls will start their periods from 10-15 years of age with the average at around 12 years.

And it is normal for girls’ periods to be irregular during puberty.

“Periods are often irregular in the early years as ovulation can be erratic initially,” explains Mr Currie. “Other factors such as weight, stress (examinations and school) can also influence menstruation,” he adds.

On average women start their periods in their teens [Photo: Getty]
On average women start their periods in their teens [Photo: Getty]


After an erratic period of, er, periods, in your teens, things should settle down in your twenties.

“Menstruation is usually its most stable in your twenties but there are conditions to consider and look out for,” explains Currie.

“Endometriosis would be the commonest condition most women are concerned about because of its impact on fertility. Endometriosis usually causes cyclical pelvic pain and increasing pain during a period.

“Many women take the combined pill not only for birth control but to help with reducing painful periods. Pain that is increasing and getting worse, especially if on the pill is a concern and should be checked.”

Switching birth control can also impact your periods.

“The ‘pill’ usually has a positive effect on the menstrual cycle,” explains Mr Pisal. “It makes the cycle regular and periods less heavy and less painful. Hence, the pill is often used as a therapeutic intervention for conditions such as endometriosis, heavy or painful periods. Occasionally it can lead to break-through-bleeding between periods.”

And according to Mr Pisal other forms of contraception can also alter your period length and flow.

  • Non-hormonal Intrauterine Devices (IUD, Copper-T) can lead to bleeding between periods.

  • Hormonal IUDs (Mirena or Jaydess) secrete a small amount of progesterone within the uterine cavity and will often lead to lighter and less painful periods. Sometimes the periods are completely blocked. Irregular bleeding in the first few months is also a common side effect.

  • The Injection Pill, Implant and minipill all contain progesterone and often lead to absence of periods. Irregular unpredictable bleeding is a known side-effect.

A missed period during your 20s, 30s or any other decade could be a sign of pregnancy, but there are other reasons a woman might skip her monthly visit from Aunt Flo including Polycystic Ovarian Syndrome (PCOS) “Polycystic ovaries are common and occur in around 22% of women,” explains Mr Pisal.

“Some women with polycystic ovaries can also have anovulation (lack of ovulation) and this can lead to a late or missed period.”

According to Mr Pisal there are several other explanations for missed periods including a hormonal imbalance; “Thyroid hormone problems or pituitary (a gland in the brain) hormone issues can cause delayed or absent periods,” eating disorders; “Anorexia can cause reduced body fat and can affect ovarian function leading to late or even absent periods,” extreme exercise “Many of the Olympic athletes often miss their periods due to reduced body fat.”

Of course, sometimes periods can be late due to no obvious reason. “Stress or long distance travel or some medications can affect the cycle too,” Mr Pisal adds.


Pregnancy and birth can impact your periods no matter your age.

“Periods are quite often heavier after having children,” Ian Currie explains. “The uterus is larger, has an increased blood supply and usually the surface area of the cavity (the part that bleeds) is greater than before pregnancy.”

Breastfeeding might also affect your monthly cycle.

“Breastfeeding stops the periods for up to twelve months,” Dr Pisal says. “But you can still get pregnant while breastfeeding, so it is best to use some form of contraception.”

“It is also not uncommon for conditions such as fibroids or polyps to develop and cause period problems after having a baby,” she continues. “So heavy, prolonged or irregular periods should always prompt a doctor’s visit.”


“In your forties, periods can quite often become disrupted,” Mr Currie says. “They can become irregular, heavy and more prolonged. Pain can increase as well.”

Currie says all of these symptoms can happen without there being anything seriously wrong but the incidence of abnormal conditions (fibroids, polyps, even cancer) all increase the older you get.

“Generally if you are in your forties and are concerned about changes it is best to get checked out,” he says.

As you age your periods can become more sporadic but also more painful [Photo: Getty]
As you age your periods can become more sporadic but also more painful [Photo: Getty]

Fifties and beyond

In this time of life, periods can become increasingly unpredictable and eventually stop.

“Menopause is the period in a woman’s life when menstruation ceases, in normal circumstances this usually occurs after the age of 45,” explains Mr Pisal.

“During this time ovarian function declines and periods become irregular, unpredictable and eventually stop. This decline in ovarian function means the decreased release of hormones oestrogen and progesterone and this change in hormone level causes menopause symptoms such as hot flushes, night sweats, mood swings, lack of libido and vaginal dryness.”

Mr Pisal says menopause is a retrospective diagnosis and is made 12 months after the last period.

“The symptoms above can point towards onset of menopause and can sometimes affect your life in a major way. It’s best to see your doctor to see if hormone replacement therapy may be a solution for you.”

Follow us on Instagram and Facebook for non-stop inspiration delivered fresh to your feed, every day. For Twitter updates, follow @YahooStyleUK.

Read more from Yahoo Style UK:

Little girl who started her periods at four will soon face going through the menopause

A fifth of British women feel uncomfortable discussing their periods with their friends

Why PMS symptoms affect some women more than others