Periods 101: What’s Normal and What’s Not?

Periods can often be a bit like an unpredictable guest at a dinner party: sometimes on time, sometimes fashionably late, and occasionally a bit too dramatic. Understanding your normal menstrual cycle is crucial, as it becomes easier to spot when something’s off. From unexpected spotting to those killer cramps, we’re here to break down what’s typical and what might need a little extra attention. 

The menstruation breakdown

Menstruation is a natural process where the body sheds the lining of the uterus if pregnancy doesn’t occur. This is part of the normal menstrual cycle and involves bleeding that exits through the vagina, made up of both blood and tissue. Periods typically begin between ages 11 and 14 and continue until menopause, which is around 51 years. A normal menstrual cycle lasts between three to five days. Along with bleeding, you may experience symptoms like abdominal cramps, lower back pain, bloating, sore breasts, and food cravings.

From start to finish: The 3 phases of your cycle

From day one to the final phase, your cycle has three distinct stages that can help you get a grip on your normal menstrual cycle duration. Let’s dive into the phases that make up your month!

1. Follicular phase: This phase starts on the first day of your period and continues until ovulation. During this time, your body produces hormones that help an egg mature in the ovaries.

2. Ovulation: Around the middle of your cycle, a mature egg is released from the ovary and travels down the fallopian tube. This is the most fertile window for conception.

3. Luteal phase: Following ovulation, hormone levels rise to support a possible pregnancy, and if no pregnancy happens, your hormone levels drop, leading to the shedding of the uterine lining (aka your period). Think of it as the ‘try again next month’ phase.

The period lowdown

The menstrual cycle is a monthly hormonal symphony led by oestrogen and progesterone, with a little help from FSH (follicle-stimulating hormone) and LH (luteinising hormone). It all starts with the brain signalling your ovaries to grow a follicle; basically, an egg-in-waiting. During this time, the oestrogen rises, thickening the womb lining like a cosy nest. Around mid-cycle, LH surges and ovulation occurs; the egg is released for fertilisation. If it doesn’t happen, progesterone levels drop, the womb lining sheds, and your period begins. A normal menstrual cycle duration ranges from 21 to 35 days, depending on your body’s own unique cycle.

What is considered normal bleeding?

Wondering if your period fits the bill of a normal menstrual cycle? You’re definitely not alone. Most women bleed for around 3 to 7 days, with the heaviest flow usually in the first two days. On average, you’ll lose about 30-40 millilitres of blood; roughly 2 to 3 tablespoons, though it may feel like more. But here’s the thing, no two cycles are exactly the same. What’s “normal” for you might not be for someone else. If your bleeding is unusually heavy, super light, or drags on beyond a week, it’s worth having a quick word with your healthcare provider.

Did You Know?

On average, women lose about 30-40 millilitres of blood, roughly 2 to 3 tablespoons, every month.

When Aunt Flo forgets her schedule

When your period doesn’t quite stick to the calendar, it’s easy to feel a bit thrown off. There are plenty of reasons why your normal menstrual cycle duration might change from month to month. Let’s explore what could be causing those unpredictable dates.

• Stress

If your period’s turning up out of the blue every month, stress might be stirring the pot. Emotional, physical, or mental stress ramps up cortisol, which can interfere with the hormones that keep your cycle running on time. The result? A shifting cycle that dances outside the normal menstrual cycle range, making your period feel a bit unpredictable.

• Extreme diet or exercise

Your period isn’t just watching the calendar; it’s keeping tabs on your lifestyle, too. Sudden weight loss, rapid weight gain, or going a bit overboard with intense workouts can all throw your hormones out of sync. These shifts can nudge your cycle outside the normal menstrual cycle pattern, making your dates feel more like a guessing game than a schedule. 

• Health conditions

If your period’s been playing fast and loose with the calendar, it could be down to conditions like polycystic ovary syndrome (PCOS), endometriosis, or hypothyroidism. These culprits can throw your normal menstrual cycle off course, leaving your cycle a bit unpredictable. If it’s been happening more often, a visit to the doctor could help you figure out what’s causing the shuffle and get things back in sync.

Menstruation during your teens to early 20s

Your first period (or menarche) usually pops up between 10 and 16. If you’ve got underarm and pubic hair, your period’s probably not far behind. In the beginning, your cycle might be a bit all over the place, irregular or varying in length, and that’s totally normal. Over time, your body will find its natural pace, and you'll get a better idea of what is the normal range of the menstrual cycle for you.

How your periods work in your late 20s to early 30s

As you hit your late 20s and early 30s, your cycle tends to find its groove. Ovulation steps into the spotlight, and you'll likely start getting the hang of when you're most fertile. It's around this time that many women start thinking about family planning. It’s all about getting to know your body better and being in sync with its natural flow.

How your periods work in your late 30s and 40s

As you approach your late 30s and early 40s, your body starts giving subtle clues that things are changing. Perimenopause, the phase leading up to menopause, starts to make its presence known. This is when your hormone levels begin to fluctuate, which can bring on changes like heavier or lighter periods, more intense PMS, or the occasional skipped cycle. Some women glide through this time with little hassle, while others experience noticeable shifts, altering their normal menstrual cycle duration.

How your periods work in your 50s

In your 50s, menopause is usually just around the corner. This is when your ovaries stop releasing eggs, and levels of hormones like oestrogen and progesterone drop. As a result, your periods may become irregular or stop entirely, and this transition can take a few years. You’re officially in menopause once you’ve gone 12 months without a period. When it hits, it marks the end of your reproductive years.

Cracking the period cycle code

Ever feel like your period’s running on its own secret schedule? You are not alone. But cracking the code isn’t as tricky as it seems. With a bit of know-how, you can figure out your normal menstrual cycle duration and keep track. Here’s how to get started. 

• Calendar method

Grab a calendar or install a period tracking app on your phone and jot down the first day of your period each month. The days between those red dot entries? That’s your cycle length. Ovulation usually sneaks in 12–14 days before your next period, and your fertile window hangs around for about a week. But if your cycle’s more freestyle than clockwork, this method might be a bit hit-and-miss.

• Cervical mucus method

Your vaginal mucus changes with your hormones, and is a handy clue for tracking fertility. Check it daily; if it’s heavy, wet, and slippery (like raw egg whites), you’re likely ovulating. Chart your findings for at least one normal menstrual cycle. It might feel a bit odd at first, so consult your doctor if you need help spotting what’s what.

• Basal body temperature method

Also known as the temperature method, this involves taking your temperature each morning before you get out of bed; no cheating! You’ll need a basal body thermometer (extra sensitive, unlike your standard one). Just before ovulation, your temperature rises slightly (about 0.3°C) and stays up after. Tracking it daily for a few months can help you spot patterns in your normal menstrual cycle. 

Parting thoughts

Getting to know your normal menstrual cycle is like learning your body’s secret language. Every cycle tells a story, and once you’ve got the hang of it, you’ll be one step ahead of aunt Flo’s monthly plot twists. Whether you're tracking for health, planning a family, or just curious, understanding your flow gives you the upper hand. Periods might be unpredictable, but you don’t have to be!

Frequently Asked Questions

1. How many days should a normal period last?

A normal period usually lasts between 3 to 7 days. If yours tends to be much longer or shorter, it's a good idea to consult your doctor.

2. Can your menstrual cycle date change every month?

Yes, your menstrual cycle can change slightly from month to month. Things like stress, changes in routine, or health conditions can cause these fluctuations. If the changes are consistent or worrying, it’s a good idea to check in with your doctor.

3. Does your menstrual cycle change with age?

Yes, your cycle can change over time. It may be irregular during your teen years, more predictable in your 20s and 30s, and shift again during perimenopause in your 40s.