The 4 Phases of the Menstrual Cycle

For most people who menstruate, the menstrual cycle is a natural part of their reproductive health that occurs each and every month and is absolutely nothing to worry about. That being said, most people who do menstruate, don’t actually know what is happening to their body during this time. The reason for this is that the menstrual cycle is a complex process that involves several physiological and hormonal changes that prepare the body for a potential pregnancy – even if the person isn’t pregnant.

It can be broken down into four distinct phases: the Menstrual phase, the Follicular phase, the Ovulatory phase and the Luteal phase. Each of these phases has its own unique characteristic and function. We believe more people need to know what happens throughout the cycle, and will explore the four phases, what happens during each phase, and how they contribute to the overall process. Whether you menstruant or not, this article should inform you as to exactly what happens throughout the cycle.

Phase 1

The Menstrual Phase

The first phase of the menstrual cycle is known as the menstrual phase, which typically lasts for three to seven days. During this time, the lining of the uterus (the endometrium) sheds as a result of decreased levels of oestrogen and progesterone in the body. This shedding of the endometrium results in the menstrual bleeding that most people are familiar with. The average person loses about 30-40 millilitres of blood during their period, but this can vary from person to person.

Aside from menstrual bleeding, some people may also experience other symptoms during this phase, such as cramping, bloating, and mood changes. These symptoms are caused by the release of prostaglandins, which are hormone-like substances that cause the uterus to contract and can contribute to discomfort.

Phase 2

The Follicular Phase

The second phase of the menstrual cycle is the follicular phase, which begins on the first day of menstrual bleeding and lasts until ovulation. During this phase, follicle-stimulating hormone (FSH) is released from the pituitary gland in the brain, which stimulates the body’s growth of follicles in the ovaries. Each follicle contains an egg, which most of us know about, but only one will ultimately be released during ovulation.

As the follicles develop, they release oestrogen, which thickens the lining of the uterus in preparation for a potential pregnancy. The increased levels of oestrogen also cause changes in cervical mucus, which becomes thinner and more slippery, making it easier for sperm to swim through and reach the egg.

Phase 3

The Ovulatory Phase

The third phase of the menstrual cycle is the ovulatory phase, which lasts for one to two days. During this phase, the mature follicle ruptures and releases an egg, which travels down the fallopian tube and towards the uterus. This process is known as ‘ovulation.’ Generally speaking, this occurs around day 14 of a ‘typical’ 28-day menstrual cycle.

The release of the egg is triggered by a surge in luteinising hormone (LH), which is also produced by the pituitary gland. LH levels peak about 24 to 36 hours before ovulation occurs, making this a prime time for conception. Some people may experience mild cramping or spotting during ovulation, but this is generally not a cause for concern.

Phase 4

The Luteal Phase

The final phase of the menstrual cycle is the luteal phase, which begins after ovulation and lasts until the start of the next menstrual cycle. During this phase, the ruptured follicle transforms into a structure called the corpus luteum, which produces progesterone. Progesterone helps to further thicken the lining of the uterus and prepare it for a potential pregnancy.

If the egg is fertilised, it will implant in the lining of the uterus and develop into a foetus. If the egg is not fertilised, the corpus luteum will begin to break down and hormone levels will drop, causing the lining of the uterus to shed once again and marking the start of a new menstrual cycle.

The menstrual cycle is a natural and complex process that plays a crucial role in reproductive health. Understanding the four phases of the menstrual cycle can help people better understand their bodies and anticipate changes that may occur throughout their cycle. It’s important to remember that every person’s menstrual cycle is unique and may vary in length, flow, and symptoms. Some people may experience irregular cycles or have medical conditions that affect their menstrual cycle. It’s always a good idea to consult a healthcare provider if you have concerns about your menstrual cycle or reproductive health.

Being knowledgeable about the menstrual cycle and its phases can help people feel more empowered and in control of their bodies. What is important to remember is that it is a natural process that shouldn’t be stigmatised, and by having open and honest conversations about it, we can work to break down barriers and improve access to menstrual health resources for all people. So, whether you’re experiencing the menstrual cycle for the first time or have been living with it for years, take the time to learn about your body and embrace the natural process of menstruation.