How each phase of the menstrual cycle may feel like and conditions that can affect the cycle

Every month, at least an egg typically matures and gets released from the ovaries. Consequently, the lining of the uterus thickens in preparation for a potential pregnancy. If fertilization does not occur, the uterine lining sheds after 14 days, resulting in menstrual bleeding. This cycle repeats itself. During this time, women feel differently depending on the phase.

Illustration of a menstrual cycle calendar

Key takeaways

  • The menstrual cycle includes a series of events that occur in a female's uterus (womb) in preparation for pregnancy. It is measured from the first day of your period to the first day of the next period.
  • People feel differently at various phases of their menstrual cycle. They may experience symptoms such as abdominal cramps, bloating, breast tenderness, fatigue, mood swings, and headaches. These symptoms may vary from person to person and also depend on the menstrual cycle phase.
  • Medical conditions, such as endometriosis and pelvic inflammatory disease, can affect how you feel during your menstrual cycle, leading to symptoms such as pelvic pain.
  • Other conditions, like polycystic ovarian syndrome and fibroids, can lead to irregular periods or heavy menses, respectively. 

The menstrual cycle is a natural process that occurs in women of reproductive age. It coincides with the ovarian cycle and involves a series of events that prepare your body for potential pregnancy. 

Changes in the levels of the sex hormones (estrogen and progesterone) released from the ovary, along with changes in the follicle-stimulating hormone (FSH) and luteinizing hormone (LH) released from the brain, regulate the menstrual cycle.

The menstrual cycle starts with the shedding of the uterine walls and ends with ovulation. It repeats when the released egg is not fertilized, and many women feel different at various stages of their cycle.

The menstrual cycle typically lasts around 28 days. However, this can vary from woman to woman. Some may have a cycle as short as 21 days, while others may have a cycle as long as  35 days, and it is considered normal. However, a variation in an individual's cycle length by more than seven days is considered abnormal.

The menstrual cycle is typically divided into two phases based on changes in the ovaries and the womb. However, the addition of the period of menses and ovulation makes it up to four.

The proliferative (follicular) and luteal (secretory) phases are the two major phases. The menstrual and ovulation phases are embedded within these two. This article will explain the “four” phases of a menstrual cycle and what happens during each phase.

Symptoms of each phase of the menstrual cycle and what they might feel like

Below are descriptions of what happens during the various phases of the menstrual cycle and what each phase might feel like for most individuals.

1. Menstruation phase

Menstruation is the first phase of the menstrual cycle. It is common for menses to last 3 to 5 days, but in some women, they may last as short as 1 day and as long as 8 days.

Also, the average amount of blood loss during this phase is about 30 milliliters of blood. This can range from slight spotting to as much as 80 milliliters. If a woman loses more than 80 milliliters of blood, it is considered abnormally heavy.

What happens during menstruation phase

During this phase, your hormone levels drop, and this decrease leads to changes in the endometrium (inner lining of your uterus). These changes cause the upper layer of the lining to break down, bleed, and get shed as blood through the cervix and vagina. This bleeding is also known as menses or period. 

What the menstruation phase might feel like and why

You might feel tired and have low energy during your menstruation. This can be due to the low level of estrogen (a sex hormone that plays an important role in reproduction). It may also result from reduced red blood cell levels if the bleeding is heavy. Also, during menstruation, you may experience other symptoms, like:

  • Headaches
  • Breast tenderness
  • Bloating
  • Mood swings
  • Irritability
  • Skin blemishes
  • Low sex drive and 
  • Cramping in the lower abdomen or lower back. 

Some of these symptoms may start some days before the menses.  

Cramping happens when the muscles in your uterus contract or squeeze to push the inner lining out from your body through the vagina. This is known as dysmenorrhoea. Some women may feel slight discomfort, while others may feel intense pain.

While pain during the menses may be normal (primary dysmenorrhoea), it may also be due to a medical condition like endometriosis and pelvic inflammatory disease (secondary dysmenorrhoea)

Menstruation symptoms are also called period flu. The hormonal changes occurring in the body during this phase can cause uncomfortable symptoms for some people and disrupt a person's normal life. However, certain hacks can help you navigate this phase and feel better.

2. Proliferative phase (follicular phase)

The proliferative phase coincides with the follicular phase of the ovarian cycle and lasts from the first day of menstruation until ovulation, which usually occurs around day 14 of a 28-day menstrual cycle. It is the longest phase and can last about 14 days, but the actual length may vary.

What happens during the proliferative phase

Following menstruation, the low estrogen level will begin to rise as the ovaries begin the process of recruiting follicles for the cycle. The changes in the hormonal level consequently lead to changes in the lining of the uterus. The inner lining of the uterus that was shed off begins to grow back, preparing the uterus and cervix for a possible pregnancy.

The follicular phase is influenced by the follicle-stimulating hormone (FSH) released from the brain. This hormone stimulates the growth of follicles in the ovaries. Many follicles will grow, but typically, only one dominant follicle will fully mature. 

This mature follicle will also stimulate more estrogen production. Due to this increase, the level of FSH will reduce, causing the remaining follicles to be reabsorbed into the body. The level of the luteinizing hormone (LH) also begins to rise at this point in preparation for ovulation.

What the proliferative phase might feel like and why

Here is what the proliferative phase may feel like:

  • You may feel your energy level increase as a result of the increase in luteinizing hormone. 
  • Your skin may be clear and smooth.
  • You may have a high sex drive.
  • You may not feel moody again. 

Additionally, this phase also creates an environment that is friendly and helpful to possible incoming sperm. 

3. Ovulation

Ovulation is the release of an egg from the ovary. It usually occurs about 14 days before the next menstrual period, which occurs within an average cycle of 28 days.

What happens during the ovulation phase

Towards the end of the follicular phase, the level of estrogen is high, causing the follicles in the ovaries to continue maturing. This increase sends a message to your brain to produce more follicle-stimulating hormone (FSH) and luteinizing hormone (LH).

When estrogen reaches a certain point, usually around 200 picograms per milliliter of blood, it triggers what is known as the LH surge. This surge causes the mature follicle to rupture, releasing the egg from the ovary.

What the ovulation phase might feel like and why

During ovulation, you may notice that your cervix produces more cervical mucus. Also, the cervical mucus becomes watery and slippery. This helps create a more hospitable environment for sperm to swim through the cervix and reach the egg in the fallopian tube.

Some people feel dull or sharp pain around this time on the side where the ovary is releasing the egg. The pain may last a few hours to a few days. 

Other symptoms a person may experience during ovulation include:

  • Improvement in mood 
  • Increased energy
  • An increased sex drive

4. Secretory phase (luteal phase)

The secretory phase coincides with the luteal phase of the ovarian cycle. It has a constant duration of about 14 days and occurs from day 14 to day 28 of a 28-day cycle.

What happens during the secretory phase

During this phase, the hormone progesterone is predominantly produced by the corpus luteum (remnants of mature follicle left behind after the release of an egg during ovulation).

The progesterone released prepares the uterus for a possible pregnancy as the lining thickens. There are also changes in the blood vessels supplying the lining of the womb in anticipation of implantation.

Towards the end of the luteal phase, if pregnancy does not occur, the corpus luteum diminishes. The levels of estrogen and progesterone are also reduced. This drop in hormone levels triggers the shedding of the uterine lining, leading to menstruation and the start of a new menstrual cycle.

But, if pregnancy does occur, the fertilized egg implants itself into the thickened endometrium, and the corpus luteum continues to produce hormones to support the pregnancy.

What the secretory phase might feel like and why

Cervical mucus typically becomes thicker and non-elastic during the secretory phase of the menstrual cycle. Progesterone is the cause of this change. The thickened mucus helps prevent sperm from entering the uterus since the period that the body is expecting fertilization has passed. 

Also, your body temperature might increase slightly during the secretory phase due to the effect of the hormone progesterone.

Medical conditions that may  affect the menstrual cycle

Certain medical conditions can affect a person’s menstrual cycle, such as:

1. Polycystic ovary syndrome (PCOS)

Polycystic ovary syndrome is a common health problem caused by an imbalance of reproductive hormones. It predominantly affects the regularity of the menstrual cycle and could lead to infertility if not properly managed or treated. 

PCOS can affect the way you feel during menstruation due to the effects of the symptoms on mental health. If you have PCOS, you may experience symptoms such as irregular or absent menstrual periods, heavy or unpredictable menstrual bleeding, lack of ovulation, and excess hair growth (hirsutism).

PCOS can also cause:

  • Thinning hair on the scalp
  • Weight gain, or obesity (particularly around the waist)
  • Acne
  • Skin tags and dark patches of skin
  • Depression or anxiety, and 
  • Poor sleep. 

2. Pelvic inflammatory disease (PID)

Infection of the inner reproductive organs (PID) can lead to dysmenorrhea, which refers to severe and painful menstrual cramps. The pain is typically intense and occurs in a recurring pattern during each menstrual cycle. 

Along with the intense cramping, individuals may also experience symptoms such as nausea and vomiting, headaches, dizziness, fatigue, sleep difficulties, diarrhea, weakness, fainting, and headaches.

3. Endometriosis

Endometriosis is a condition where tissue similar to the lining of the uterus grows outside the uterus. This can affect how you feel during your menstrual cycle. Endometriosis can cause severe inflammatory reactions and the development of scar tissue, which can result in symptoms like severe pelvic pain (dysmenorrhoea), especially during menstrual cycles.

People with endometriosis might also feel pain during or after sex and pain when urinating or defecating. Other symptoms of endometriosis may include: 

  • Heavy bleeding
  • Bloating
  • Nausea
  • Fatigue, and 
  • Feeling depressed

While symptoms often improve after menopause, this may not always be true.

4. Uterine fibroids

Uterine fibroids are non-cancerous growths in the muscles that line the womb. They can lead to heavy bleeding during menses. This could reduce the red blood cell level, resulting in symptoms like dizziness, headaches, and difficulty breathing.

When to speak with a gynecologist

It is important to speak with a gynecologist if you suspect you may have any of the medical conditions that affect the menstrual cycle, as discussed in this article, or if you experience unusually severe symptoms during your menstrual cycle. They will provide accurate diagnoses and recommend appropriate treatment options to help manage your symptoms.

Frequently Asked Questions (FAQs)

In which phase of the menstrual cycle does implantation occur?

Implantation typically occurs during the later phase of the menstrual cycle, called the luteal phase. After ovulation, if fertilization occurs, the fertilized egg attaches itself to the prepared lining of the uterus, known as the endometrium.

Does the menstrual cycle start at the beginning or end of period?

The menstrual cycle starts at the beginning of your period. You start counting from the first day of your period and end a day before the next period.


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  4. NHS. UK (2022) Symptoms Polycystic Ovary Syndrome
  5. National Institutes of Health (2023) Dysmenorrhea 
  6. World Health Organization (2023) Endometriosis