There is blood in my knickers. Again. Normally I’m quite good at catching my period, at realising exactly when it is arriving and making it to the bathroom in time to push a tampon in but on this occasion it has surprised me, first thing in the morning, and there is a tiny red puddle in between my legs.

Periods have a bad reputation. This isn’t without reason. Far from the glossy adverts of women in bright white shorts climbing mountains or playing tennis, there are many awful things about having a period. Sometimes I wake up with cramps so severe that I can’t get out of bed. On those days I can’t work, can’t read, can’t concentrate. Rowing or playing netball — my two main sports — are impossible without round after round of painkillers. I lie upside down in bed, back against the mattress, legs against the wall and concentrate on the inside of my body. It is that same sort of sharp pain as when you hit your toe against a wall or the corner of a bookshelf. The same kind of pain as food poisoning — or just regular poisoning, I imagine.

“Since coming off birth control, I have realised how important to me my period is”

When I am on my period, I often gain a kilo or two in water weight. My tummy gets hard and bloated for a few days, stretched taut like the skin of a drum. When I am on my period, I cry at things that wouldn’t normally get to me. Sometimes I cry for no reason at all. And of course, when I am on my period I sometimes ruin a nice pair of knickers or an expensive pair of jeans because I have left a tampon in a little too long or forgotten to put one in to begin with. In my red flush I have to rub Vanish into my clothes, soak them, and then grapple with the ever-complicated Circuit laundry app to put a wash on, when all I really want to do is sit very still with my eyes closed.

For a number of years, I was taking the contraceptive pill, so I didn’t have a period. I had my seven-day withdrawal bleed, after each twenty-one day course of pill-taking, but this wasn’t the same. I could skip it if I wanted, for a start. You can’t skip a period. If the withdrawal bleed days didn’t line up with the rest of my life, I could just opt out. Who wants to be bleeding during their A Level exams or on the night of their anniversary with their boyfriend? If it wasn’t convenient then I didn’t have to have it. There were other obvious benefits to being on birth control too: no mood swings, no cramps, no baby. I don’t regret being on it for so long. But I can’t deny that I missed my period.

“I remember each and every time that I will never be as young as I am at this very moment, crouched over in the bathroom”

Since coming off birth control, just to return to a hormone-free existence for a while, and to feel the highs and lows of everyday life more acutely, I have realised how important to me my period is. There is some significance in being reminded every twenty-eight days, when my period arrives again, that twenty-eight days have passed. For those who don’t think of it in these terms, this might seem scary. To be forced to reflect on what I have achieved or not achieved every four weeks is certainly hard sometimes, when very little of significance has happened. But it is a calendar that I am grateful for. It compels me to evaluate, to move forwards, to grow.

A lot can change in twenty-eight days. You can start dating somebody new. And stop dating them. You can get good news, bad news, life-changing news. You can pick up a new sport or get miles better at the one you already do. You can learn to cook, learn to drive, even begin to learn a new language. Normally my twenty-eight-day blocks are not quite that dramatic or eventful, but I do always feel like a more refined version of myself than the me I was when my last period arrived. I remember each and every time that I will never be as young as I am at this very moment, crouched over in the bathroom.

I don’t want to have a baby right now — no way — but I don’t think that when one day I do, it will be the case that all my years and years of periods will suddenly seem to have been worthwhile. Even now, they have value. I love living my life in cycles that are four weeks long. I love being reminded every twenty-eight days that I am young and healthy, and most of all that I am four weeks older and wiser than I was when I was last bleeding into my knickers.