Menstrual Cycle 101

Aug 30, 2024

Originally published 7/2/2020

It’s such a shame how little we are taught about our menstrual cycle and our body in general.

Understanding your menstrual cycle, your hormones and your ever-changing body is one of the most empowering things I can think of for a woman.

And I’m ALL about empowering women!

If you’re like me, you probably learnt very little about your body and your cycle during health class!

Seriously, all I remember from those lessons (apart from putting condoms onto banana’s) was having the idea that I could get pregnant ‘any day of the month’ drummed into me…..which is totally wrong by the way!

Women aren’t fertile 100% of the time so it’s impossible for us to get pregnant "all the time!"

Don’t worry if you didn’t know this. Or if you don’t really understand what’s happening with your body at all.

I’ve got you sister.

The life cycle of women

Firstly, let’s cover the big picture – the overall life-cycle of a woman’s fertility and hormones. I’ve broken them down into the basic life phases.
⠀
These ‘phases’ of life can occur at very different times for each individual woman so the ages noted are just averages.

PUBERTY
Her breasts start to develop, hair grows in new places, sweat glands kick into gear, genitals usually change shape and vaginal discharge begins, often noticed on her undies.⠀

MENARCHE
The official start of fertility is marked when her first period arrives. This is known as Menarche and I'd personally love to live in a world where this is celebrated!

REPRODUCTIVE YEARS
The years in which she is ovulating and able to become pregnant.

PERI-MENOPAUSE
The transition to menopause which begins with declining hormone levels and often lasts several years.

MENOPAUSE
Menopause is 1 day - the 12 month anniversary of her last period. She has officially moved out of her fertile years.⠀

POST-MENOPAUSE
The time after menopause until death.

woman in black blazer sitting on concrete bench

With each of these phases comes new things to learn about our bodies, remember that the ages are a guide only.

Menstrual Cycle basics

The menstrual cycle is the hormonal cycle a female’s body goes through each month to prepare for pregnancy.

Each cycle there are hormonal and physical changes. Some key ones to note are the development of follicles containing eggs (in the ovaries) and the thickening of the uterus lining in case the egg is fertilised after ovulation and needs to embed into it.

If the egg isn’t fertilised then the lining of your uterus breaks down and leaves your body so that it can renew again next month.

This whole process is a cycle that repeats over and over during your fertile years.

The 4 phases of the menstrual cycle

There is so much more to your menstrual cycle than just your period. In fact, your period is only 1/4 of the whole cycle and it’s not even the main event!⠀

The 4 phases your body goes through each cycle are menstruation, the follicular phase, ovulation and the luteal phase.

Menstruation
Menstruation is a woman’s monthly bleeding and we often call this a “period.” The bleeding is a result of the lining of the uterus breaking down and leaving the body.

Follicular phase
This phase starts once your period has finished. It’s called the follicular phase because this is when the follicles on your ovaries are growing and maturing, getting ready for one of them to release an egg at ovulation,

Ovulation
This is the main event of your menstrual cycle! During ovulation, the most dominant follicle on one of your ovaries will rupture and an egg will be released into your fallopian tube – this is called ovulation and in a “typical cycle” it usually occurs around day 14.⠀

Luteal phase
This phase refers to the time between ovulation and the start of your next period. If your egg doesn’t get fertilised within 24 hours of ovulation, it will die and this leads to an eventual drop in your estrogen and progesterone levels. As these levels drop, the lining of the uterus breaks down and then you get another period.

What a typical cycle looks like

It’s really important to know that a normal menstrual cycle can look very different for each of us because there are actually ranges that fit into the ‘normal’ classification.

Menstrual cycle length
The length of your menstrual cycle is determined by counting from the first day you have your period, until the day you get your next period.

When you first start bleeding that is Day 1 of your cycle. But, it needs to be proper red blood flow – if you get spotting that is not the start of a new cycle.

The ‘typical menstrual cycle’ is almost always referred to as being 28 days long, however the International Federation of Gynecology and Obstetrics concluded that a cycle length anywhere from 24 to 38 days is normal.

If you’re a teen, your cycle can be up to 45 days long and still be considered normal.

Ovulation
Typically we are taught that we ovulate around day 14 but it’s different for every woman and it can be different from one cycle to the next.

When you ovulate there are only two possible outcomes – you will either get a period 10-16 days later, or you will become pregnant.

Period length
The average period is about 3-5 days and this includes the lighter bleeding or spotting at the end when your period is finishing up.

It’s considered normal to have a period anywhere from 2-7 days. If your period is longer or shorter than this, it indicates you have an imbalance.

Period bleeding
Menstrual fluid is not just pure blood. It also contains cervical fluids and bits of uterine lining that have shed as a result of your egg not being fertilised.

Your period blood should be mostly fluids and shouldn’t contain large clots. If you do have some small clots this isn’t something to worry about, but if they are larger than about a five-cent piece (2cm) then that’s not considered a normal part of menstrual bleeding.

The colour of period blood can vary from light pink, bright red, deep red or brown and still be considered normal.

A healthy amount of menstrual fluid is about 50ml or 2 ½ tablespoons. If you lose less than 25ml or more than 80ml this is outside the normal ranges.

As a guide, one soaked regular pad or tampon holds 5ml. A super tampon holds 10ml. To get a pretty good idea of how heavy your flow is, add up the total amount of bleeding over the full length of your period if you only half soak a pad or tampon, adjust your calculation)

What your hormones are doing during your menstrual cycle

The graph below shows four of the key hormones involved in the menstrual cycle. You can see how they all change dramatically during a typical 28-day cycle.

Here’s the quick rundown of what this all means inside your body (note – there are other hormones involved too but this post is just covering the basics):

Shortly after your period starts, you’ll produce estrogen and follicle-stimulating hormone (FSH).

Estrogen plumps up your uterine lining in preparation for pregnancy and FSH tells your ovaries to start maturing the follicles.

Estrogen keeps rising and then once it hits a certain level this signals to the pituitary gland to produce a surge of luteinizing hormone (LH).

Around 24-36 hours later, the surge in LH causes the most mature follicle to rupture and an egg is released into the fallopian tube – this is ovulation!

The follicle left behind on the ovary is now called the Corpus Lutem and it quickly starts producing Progesterone.

There’s a second small surge in estrogen after ovulation but progesterone should remain the dominant hormone after ovulation.

If your egg isn’t fertilised, the corpus luteum is reabsorbed into your ovary and the drop in hormones signals for your uterus lining to shed.

This causes your period to start and the whole magical cycle begins again!