How many phases does the menstrual cycle have?

We use this classification to refer to the main activity and hormone at any point in the menstrual cycle.

It begins on the first day of your period and lasts until ovulation.

The primary activity during this phase is the development of follicles in preparation for ovulation. The dominant hormone during this phase is estrogen. The length of the follicular phase can vary due to stress, illness, weight changes, and other events that might delay ovulation.

It starts one day after ovulation and ends the day before your next period.

The primary activity during this phase is the development of the corpus luteum, a small gland responsible for producing progesterone—the dominant hormone in this phase—following ovulation.

The luteal phase typically has a fixed length of 12-16 days.

This classification is mainly used to identify the fertile and infertile times in the cycle. Understanding when your fertile window opens and closes can give you knowledge about your reproductive potential and support you in your family planning decisions.

It begins on the first day of your period and ends once your fertile window opens.

During this phase, both estrogen and progesterone levels are low. It’s considered an infertile time as follicular development has not yet started.

The duration of this phase can vary due to stress, illness, and other events that might delay ovulation. The longer (or shorter) your cycle is, the longer (or shorter) your pre-ovulatory phase will be.

It begins on the day you notice the presence of estrogenic cervical mucus (in the FEEM Fertility Awareness Method we call this, ‘the Point of Change’), and ends when you confirm ovulation*.

This is the time in your cycle when conception is possible. You need a viable egg, sperm, and estrogenic cervical mucus to conceive a baby—these three things can only be present simultaneously during the ovulatory phase. Estrogenic cervical mucus helps sperm survive and travel to the uterine tubes where fertilisation would potentially happen.

This phase has an average length of 6 days. In other words, you’re only fertile for about 6 days in your cycle. That’s it!

It starts the day after you confirm ovulation* and ends the day before your next period.

During this phase, progesterone becomes the dominant hormone. Triggered by progesterone, your cervix produces a dense mucus plug that prevents the entry of sperm and bacteria into your uterus. This phase prepares your uterus for either your period or pregnancy, and it’s an infertile time; in other words, there’s no chance to get pregnant anymore.

This phase has a fixed length of 12-16 days.

*Please note that this is based on the FEMM Fertility Awareness Method guidelines, and the delimitation of the ovulatory phase may vary depending on the accuracy of the method used to identify ovulation: cervical mucus, ultrasound, blood, or urine. Fertility Awareness Methods will usually give you a more conservative delimitation. Learn more in my Free webinar: What are Fertility Awareness Methods and how can they help me understand my cycle.

This classification is mainly used in the realm of Menstrual Cycle Awareness to recognise the physical, mental, and emotional changes that you experience in each phase of your cycle, mirroring the seasons of the year and other cycles in nature.

Inner Winter / New Moon / Seed

Your period!

This phase is a reset for your body—a time for renewal and healing, during which you may feel the need to rest and disconnect from the outer world to reconnect with yourself.

A healthy period length is considered to be 3-7 days.

Inner Spring / Crescent Moon / Sprout

It begins one day after your period ends and continues until your fertile window opens.

Thanks to estrogen, your energetic hormone, motivation, physical strength, and energy gradually increase during this phase.

The length of this phase can vary due to stress, illness, and other events that might delay ovulation.

Inner Summer / Full Moon / Bloom

As estrogen reaches its peak, you feel more energetic, confident, and magnetic. A slight surge in testosterone increases your libido, motivation, and physical strength.

On average, this phase lasts for six days.

Inner Autumn / Waning Moon / Decay

It begins one day after ovulation is confirmed and ends the day before your next period.

Progesterone, your calming hormone, makes you more introspective, sensitive, and vulnerable. You’ll find yourself beginning to wind down. PMS challenges such as bloating, breast tenderness, headaches, anxiety, and moodiness can emerge as a result of an imbalance between estrogen and progesterone.

This phase has a fixed length of 12-16 days.

I hope this explanation has given you more clarity on the different ways to divide the menstrual cycle.

In summary:

• The follicular and luteal phase classification can simplify things focusing on the dominant hormones and activities that shape each stage. It’s a practical approach, especially if you’re tracking ovulation or hormonal changes for specific purposes.
• If you seek a deeper understanding of your fertile window either because you’re looking to get pregnant, avoid a pregnancy, or monitor your hormonal health, the three-phase perspective—pre-ovulatory, ovulatory and post-ovulatory—classification will be helpful.
• And if you want to embrace the physical, emotional, and mental changes in each phase, aligning them with the cyclical patterns of nature, the four-phase classification—menstrual, pre-ovulatory, ovulatory and premenstrual—will give you lots of insights.

Whether you focus in two, three, or four phases, the key is understanding your body’s rhythm and gaining insights into your hormonal and reproductive health.

As always, I’m happy to answer all your questions. Comment below or send me a DM on Instagram @carlorenzana.