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20th Feb 2019

Here’s what happens on every day of your menstrual cycle (roughly)

The average menstrual cycle is about 28 days.

There are also 28 days in the average month of February, which is handy enough considering we’ve decided to dedicate an entire month to all things periods. 

And despite learning it off by heart for Leaving Cert biology, so many of us are still mildly confused as to what actually happens on each day of the menstrual cycle.

Questions like ‘when do I actually start ovulating?’ and ‘how long does it take the lining of the womb to build up?’ are specific to each person and the length of their individual cycle, but once you’ve got an idea as to the order in which these things happen, keeping track of your cycle can actually end up being really easy.

As we all know, no two menstrual cycles are going to be exactly the same.

So while the length of the average cycle is about 28 days, and the things that happens inside of the body are probably going to be similar enough to the below, some people have longer cycles and some people have significantly shorter ones.

The order of things that happen, however, is going to be very much the same irrespective of the how long or short your cycle is.

So, buckle up, brace yourself, work out what day you’re on in your cycle – and get ready to know exactly what’s going on in your uterus right now.

It’s good to track these things, y’know?

Day 1: The lining in your uterus starts breaking down and leaving the body. This is the first day of your period and your flow is probably going to be pretty heavy.

Day 2: Your hormone levels are fairly low at this stage, so you’re likely to be more irritable and easily annoyed. Your period, of course, continues.

Day 3: A lack of oestrogen can make you feel pretty upset, annoyed, and generally unhappy. Your period, of course, continues.

Day 4: During your period, follicles full of fluid start to appear on your ovaries. Each of these follicles contains an egg waiting to be released.

Day 5: One follicle containing an egg grows a lot larger than the rest. She waiting. She ready.

Day 6: The other follicles become smaller and disappear back into your ovaries, while the larger one containing an egg keeps growing.

Day 7: Your oestrogen levels continue to rise while the follicle containing the egg grows even larger.

Day 8: Your period has probably stopped by now. More oestrogen is finally starting to make you feel less irritable, thank god.

Day 9: Increased levels of oestrogen continue to make you feel less irritated, while also start to build up the lining in your womb again.

Day 10: The uterine lining starts preparing itself to nourish any incoming egg that might be fertilised. It thickens with the intention of latching an egg to it.

Day 11: The days just before the egg is released – and the day it is released – are your most fertile. So, usually between days 11 – 14, but again, this depends on how long your cycle is.

Day 12: Your oestrogen levels are probably at their highest now, making you feel pretty good, emotionally and physically. And fertile. Very fertile.

Day 13: The follicle is about to burst to release your egg.

Day 14: The egg is released – you’re ovulating! You’re also most likely to get pregnant if you have sex on this day (or the three days before).

Day 15: The burst follicle makes the uterine lining even thicker. Your egg begins its journey through the fallopian tube.

Day 16: Your egg is traveling along the fallopian tube.

Day 17: Your egg is traveling along the fallopian tube.

Day 18: Your egg is traveling along the fallopian tube.

Day 19: Your egg is still traveling along the fallopian tube.

Day 20: Your egg is still traveling along the fallopian tube.

Day 21: If your egg is joined by a sperm while travelling in the fallopian tube, boom – the egg is fertilised.

Day 22: If your egg is fertilised, it and the sperm continue along the fallopian tube to the uterus together. Remember, sperm can survive up to five days inside the female body.

Day 23: Your egg is almost at its destination – the womb.

Day 24: The fertilised egg attaches itself to the lining of the womb. If the egg isn’t fertilised, it breaks up.

Day 25: If your egg is fertilised, it will start to grow inside the womb. Massive congrats to all involved, you’re pregnant!

Day 26: Your hormone levels will have dropped a lot by now if you’re not pregnant. You’ll feel irritable (again) as your oestrogen decreases.

Day 27: The egg and uterine lining realise there’s no pregnancy. There’s no need for them anymore.

Day 28: Your unfertilised egg is waiting to be released in the form of your period.

Aaaand then you’re back to Day 1: the beginning of your menstruation cycle – and it’s time to do it all over again. 

For the month of February, Her will be #OnTheRag. 

We’ll be chatting all things periods, products, and pain as we delve deep inside the uterus to figure out why we bleed and – more importantly – how we cope.

We’ll also be talking to the experts about some of the period related conditions you have heard of – and all of the ones that you haven’t. 

You can follow the rest of the #OnTheRag series here or follow our Instagram account for more period related content. 

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