Menstrual Cycle 101
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Menstrual Cycle 101

by Guest Blogger
Menstrual Cycle 101

Periods, bleeds, “Aunt Flow,” that time of the month...chances are if you’re here that you have a menstrual cycle or know someone who does. But what exactly is a menstrual cycle?

People who have menstrual cycles are always somewhere within that cycle. The menstrual cycle is more than the days of menstruation, or the period. It consists of four phases: menstruation, the follicular phase, ovulation, and the luteal phase.

In most cycling people, these four phases will repeat regularly (around every 21-35 days) until levels of the reproductive hormones decline in menopause. These phases provide a roadmap for life, creativity, productivity, and rest, whether we are using the current menstrual cycle to conceive a child, birth a business, grow personally, or bring about collective change in the world.

It’s revolutionary and beneficial to understand the phases of the menstrual cycle, and it’s also important to acknowledge that there are many variations of this cycle. Though the menstrual cycle follows a specific pattern, it may look different between people or over the course of a lifetime. These differences may be variations influenced by biology, personality, lifestyle, circumstance, environment, etc. or they could be due to issues like polycystic ovary syndrome (PCOS) or endometriosis.

With that in mind, here are the four phases that make up the menstrual cycle:


The cycle begins with menstruation, or the first day of the cycling person’s period. For those tracking their cycles, the first day of a period bleed is the day to begin a new chart. During menstruation, hormones are at their lowest as the body sheds the lining of the uterus (the endometrium) to begin a new cycle. Many bleeding people feel more introverted during this time. Depending on personality, personal values, hormones, life situation and circumstance, relationships, etc. this introversion can manifest as everything from irritation, moodiness, sadness, anger, or grief to intuition, vision, and inspiration, and everything in between. Generally menstruation can be considered a time of release, for body, mind, and energy.

For comparison purposes, menstruation is similar to midnight if we think about a 24-hour daily cycle. At midnight your body is typically tired or resting, and you may feel a need to release or turn inwards, and menstruation is similar.

Follicular Phase

The follicular phase is the second phase of the menstrual cycle, though in reality it begins with menstruation but typically outlasts the period bleed. The period is an event in the cycle, and the follicular phase is a phase that encompasses that event. The follicular phase can be considered the “first half” of the menstrual cycle, though the two "halves" of the cycle may not be the same number of days for every person, every cycle. During the follicular phase, the body employs hormones to stimulate the growth and maturation of eggs (and their “shells,” called follicles) to prepare for the release of one or more eggs at ovulation. Hormone and energy levels rise during this time, creating a phase during which many people feel more active and energetic.

Going back to a 24-hour daily cycle, the follicular phase can be thought of as midnight to noon. We likely begin this segment of time resting and laying low while the body mends, heals, and sheds during sleep, and then eventually wake up as our energy builds and we begin the day.


Like menstruation, ovulation is more an event than a phase. Ovulation itself may only last for a few minutes, and the egg(s) live in the body for 12-24 hours. During ovulation, hormone levels peak to prompt the release of the mature follicle(s) and these high, ideally balanced, levels of hormones typically contribute to heightened sex drive and energy. Many people love how they feel around ovulation and notice the effects of heightened hormones, energy, and sexuality in their bodies and minds. However, it's also the case that this high energy can be overwhelming or frustrating. There's no prescribed way to feel or experience any event or phase of the menstrual cycle, so tuning into your body and experience is key.

If we place ovulation on a 24-hour clock, it makes sense to compare it to noon. During ovulation, and similarly around 12PM, things are bright, peaking, and often intense. We may feel a burst of energy, the sun shines bright, and the day is in full-swing.

Luteal Phase

The final phase, or “second half” of the menstrual cycle is the luteal phase. This phase begins after ovulation and lasts until the first day of the next menstrual bleed. During this time, if egg(s) have been fertilized by sperm, implementation of an embryo leading to pregnancy may occur. During the luteal phase, hormone levels rise and then begin to fall. As they drop, cycling people may notice intense effects in their bodies, emotions, and energy levels. Premenstrual Syndrome, or PMS, may occur during this time. PMS may be physical, emotional, or behavioral, and can include everything from bloating, breast tenderness, and cramps to anxiety and mood swings to forgetfulness and exhaustion. Though some people experience an inner knowing or intuition from the earliest days of conception and may experience signs or symptoms of implementation, it’s worth knowing that many of the symptoms that occur during the luteal phase occur whether a pregnancy is underway or not. During the luteal phase, the body prepares to shed what it no longer needs.

Finishing out the comparison between the menstrual cycle and 24-hour daily cycle, the luteal phase compares well to the span of time between noon and midnight. We begin this phase at peak energy levels, and from there wind down and head towards rest and release, in the evening hours, or through a new cycle beginning with menstruation.

If you thought that the menstrual cycle was only the days of your period, it might sound overwhelming or exhausting to learn that people with a menstrual cycle are in that cycle for years of their lives, from puberty to menopause. The good news is that each part of the menstrual cycle is different, and learning more about your cycle can help you thrive, physically and mentally, in each and every phase.


Beth Rich is a queer educator and lifespan doula who works at the thresholds and intersections of menstruation, family-building, pregnancy, birth, loss, and other life transitions. She's a non-binary human who's excited to talk about bodies, periods, birth, and sex in language that holds space for all of us. Discover more of her work at or on Instagram @thebethrich.

Photo by Alessandra Caretto on Unsplash

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