Understanding Your Cycle: The 4 Phases of the Menstrual Cycle

Most of us know the basics of the menstrual cycle: A “normal cycle” is between 24-38 days, starting with day one of your period and ending when the next period begins. But what the heck happens during the time in the middle? Turns out, there’s a lot going on inside your body while you’re in-between periods.

We’re breaking down the four phases of the menstrual cycle with basic explanations, along with how each phase likely impacts you both physically and mentally.

Phase 1: Menstruation 

Day 1 of your cycle is marked as the first day of your period. During menstruation, the egg from your previous cycle isn’t fertilized, resulting in a drop in estrogen and progesterone. This drop leads to the lining of your uterus “shedding” and the start of your period. 

Physically: Many people experience breast tenderness, cramps, headaches, an increase of acne, and digestive changes during this phase. Interestingly, strength is often increased during menstruation, as your body has lower amounts of estrogen during this time! 

Mentally: If you feel moody AF during your period, you’re not alone! Symptoms such as anxiety, irritability, and depressed moods are extremely common, although they typically decrease as your period progresses. Menstruation is also often accompanied by fatigue, so be sure to take it easy and listen to your body during this phase! 

Phase 2: Follicular Phase

The follicular phase actually begins at the start of your period, and ends with ovulation. During the follicular phase, the body produces FSH (follicle stimulating hormone) from the pituitary gland. With this, the ovary produces follicles, each of which contain an immature egg. Typically, one egg will mature during the follicular phase, around day 10-28 of your cycle. 

Physically: The two(ish) weeks of the follicular phase are often the best weeks of your cycle when it comes to energy levels. Many health experts recommend making the most of the follicular phase by engaging in regular exercise during this time.

Mentally: Brain fog, be gone! The follicular phase is often accompanied by a mental clarity and increased creativity that we typically lack during the menstrual phase. (Cue: “I can see clearly now, the rain is gone”)

Phase 3: Ovulation

During ovulation, the mature egg produced during the follicular phase is released from the ovary. This occurs roughly 2 weeks before your next period is set to begin. A mature egg has a lifespan of about 24 hours after ovulation. This is called the “fertile window.” During ovulation, the uterus lining is thickened to prepare for a potential pregnancy, making a cozy spot for a fertilized egg to be implanted. 

Physically: Many experience ovulation discomfort, another unwelcome symptom of the menstrual cycle. Even if you don’t have this, ovulation can be marked by breast tenderness, bloating, and appetite changes. You might also notice an increase in cervical mucus during ovulation. Fun times! 

Mentally: Mood changes during ovulation are common as your body adjusts to changing hormone levels. On the plus side, ovulation often leads to increased energy levels and many actually feel their best during this phase! 

Phase 4: Luteal Phase

The ruptured follicle (which the mature egg was released from during ovulation) forms what is called the corpus luteum, a group of cells that produce progesterone. The corpus luteum maintains the thickened lining of the uterus – think of this phase like your body patiently waiting to find out if the egg will be fertilized or not. If the egg isn’t fertilized, the corpus luteum withers – usually around day 22-28 of your cycle. The resulting drop of progesterone results in the lining of your uterus shedding, and your menstrual cycle starts again with day 1!

Physically: Estrogen levels are high during the luteal phase, often resulting in similar symptoms that you might experience during your period such as acne, headaches, and breast tenderness. 

Mentally: PMS rears its ugly head during the luteal phase, where you’re most likely to experience mood swings, anxiety, irritability, and all. the. emotions. The good news? Many of the more severe symptoms of the luteal phase decrease at the start of your period. 

The more you know…! 

Are there any period problems you’re curious about? Comment below and let us do the research for you!