It happens once a month, but what goes on behind the scenes remains a mystery for many. Alex Casey goes on a search for answers about what really happens during the menstrual cycle. 

A menstrual cycle is a lot like Rihanna’s Super Bowl performance – and not just because she was dressed in blood red surrounded by hundreds of dancing pads. Just as many of us checked our calendars fervently for her arrival and then cleared our schedules to watch the halftime show, we tend to think of bleeding as the “main event” of the cycle. We don’t tend to think about the months of rehearsal, the costume fittings, or the elaborate stage packdown quite as much. 

Just as understanding the behind-the-scenes details of the halftime show will give you a whole new appreciation for Rihanna’s Super Bowl performance, there’s also huge benefits to knowing what is going on behind-the-scenes on either side of The Big Bleed. “The menstrual cycle is this really orchestrated, beautiful hormonal thing,” gynaecologist Dr Michelle Wise explains. “We typically talk about a 28-day menstrual cycle, but a lot of the actual details get skipped at school.” 

Learning about what happens in the leadup to your period can give us a better understanding of the physical and mental changes we might experience during a typical cycle, and how to better take care of ourselves throughout. “People need to be mindful of what their own normal cycles are, so that they can start to recognise if there’s a problem or anything out of the ordinary,” says Wise. So, without further ado, here’s your guide to the four (!) phases of your menstrual cycle. 

Part one: The Menses phase

The phase you are probably the most familiar with is menses, the bleed, which sees the tissue and blood of the endometrial lining exit the body via the cervix and vagina, usually for around a week. But it’s not all about what is happening downstairs, Wise says – the hormonal dip can mess with your upstairs regions too. “For example, some people who get headaches or migraines will notice them more in the parts of the cycle where the oestrogen levels are low.” 

Other side effects can include feeling bloated, cramping and sore breasts. Wise says cravings are “not scientific” enough to mention, but did want to reiterate that some heavy bleeding is cause for concern. “The most common thing that we see here is that people normalise having really heavy periods,” she says. “I feel so bad that people go for months or even years without seeking medical attention, because it’s such an easy thing to get on top of.” 

And there are now so many options for period products to suit different lifestyles – gone are the days of pads and tampons being the only choices. Options like cups and underwear have given people a broader selection to suit every period experience, while the technology used in more traditional products are getting better too.

Part two: The Proliferative phase

Oestrogen rules this part of your menstrual cycle, which happens after menstruation and before ovulation. “Here, there’s the hormones at the level of the brain that are acting on the hormones at the level of the ovary, which is acting on the endometrial lining on the inside of the womb,” Wise explains. The increase in oestrogen leads to a thickening of the lining of the uterus as it prepares the VIP room for one very special guest (an egg). 

Wise says this is the most variable part of the cycle. “It can be anywhere from one or two weeks to three to four weeks,” she explains. If the phase lasts for an elongated amount of time, the endometrial lining will continue to get thicker and thicker, which Wise says leads to prolonged, heavier periods and more clotting. “Medically, we’d use progesterone here to try to make that lining a bit thinner, so that you’re not bleeding as much, and it’s not as therefore not as long and not as painful. That’s how those two things connect.”

Part three: Ovulation

Rather poetically, Wise describes ovulation as a “moment in time” when the ovary releases the VIP egg. “So this is the shortest phase because it happens very quickly,” she says, “but it does cause a surge in the luteinizing hormone (LH).” The impacts of this phase are less about mood and more about physical changes. “People can often tell when they’re ovulating by changes in their vaginal discharge and their temperature,” says Wise.

To put things bluntly, things are going to feel warmer throughout your entire body and wetter, clearer and more slippery downstairs. 

Part four: The Luteal phase

In the final part, progesterone rules the roost. “This is the time that your womb or your uterus is really getting ready for pregnancy,” says Wise. “If a fertilised egg comes along and implants in the uterus you are going along the pregnancy pathway and, if not, your body prepares to shed that lining.” As the progesterone levels start to fall towards the end of this phase, Wise mildly suggests that “people might notice changes in their mood.” 

For some that might mean crying at a picture of a smiling volcano, while others might not notice at all. Unlike the proliferative phase, the luteal phase is generally consistent from cycle to cycle, clocking in at around two weeks for most. If your egg is unfertilised, your body recognises that it no longer needs to keep the VIP lounge stocked, and your womb prepares for menstruation, aka heading back to part one. In the words of Wise, a “beautiful and orchestrated” process indeed. 

This content was brought to you in partnership with TOM Organic. Find out more about their range of products and learn more about your cycle on their website now.