Menstrual Cycle Basics

Every body is different.

Because of this, every person may experience having a period slightly differently. Knowing the basics about the menstrual cycle can help you recognize patterns in your cycle and know what to expect. This page just scratches the surface on all there is to know about the menstrual cycle. Check out the basics below and stay tuned for a deeper dive! 

Menstrual Cycle Length

The length of a menstrual cycle, or the time between periods, can vary from person to person. It is common to get a period every 21 to 35 days and each period can last anywhere from 2-8 days. It is likely for there to be fluctuation between cycles and that is ok.  Similarly, the symptoms experienced throughout the cycle can vary among individuals. As our hormone levels alter throughout the cycle, it is common to experience symptoms like cramping, increased hunger, tenderness in breasts, mood fluctuations, fatigue, headaches.

Menstrual Cycle Phases

The body is constantly moving through the three phases that make up the menstrual cycle. The natural rise and fall of specific hormones drive the shift from one phase of the cycle to the next. Hormones act as messengers traveling through the blood to organs and tissues allowing them to perform essential functions. 

  • Follicular Phase
  • Ovulatory Phase
  • Luteal Phase

The first day of your period, or bleeding, signifies the start of the follicular phase. This can last for 10-16 days. 

The next phase is the ovulatory phase which lasts anywhere from 16-32 hours.

The last phase of a menstrual cycle is the luteal phase lasting approximately 14 days.

Menstrual Irregularities 

Keeping track of your period and its patterns is a powerful way to stay in tune with your body and notice if there have been significant changes to your cycle. Missed periods or lack of a period can be a sign that your body is not receiving the fuel it needs. Additionally, irregular periods can result from various medical conditions. It is always important to meet with a medical professional to understand WHY the reason for missed periods. There are a few ways to categorize irregular periods. 

  • Oligomenorrhea
  • Primary Amenorrhea
  • Secondary Amenorrhea

Having less than 6-8 periods per year. This can also be thought as a menstrual cycle that is consistently longer than 35 days. 

When an individual has not had a menstrual cycle by the age of 15

When a regular menstrual cycle stops occurring for more than 3 months OR when an irregular menstrual cycle stops for more than six months

Periods are Powerful

Let’s be real, periods can certainly feel like a hassle. In addition to the symptoms that come with it, making sure you have enough tampons, pads, period underwear (and the list goes on) with you can feel exhausting! Even so, we truly believe periods are something to be celebrated and embraced.  Periods are a great sign that your body is likely being properly fueled and rested.


Bull, J.R., Rowland, S.P., Scherwitzl, E.B. et al. Real-world menstrual cycle characteristics of more than 600,000 menstrual cycles. npj Digit. Med. 2, 83 (2019). 

Klein DA, Paradise SL, Reeder RM. Amenorrhea: A Systematic Approach to Diagnosis and Management. Am Fam Physician. 2019 Jul 1;100(1):39-48. PMID: 31259490.

Reed BG, Carr BR. The Normal Menstrual Cycle and the Control of Ovulation. [Updated 2018 Aug 5]. In: Feingold KR, Anawalt B, Boyce A, et al., editors. Endotext [Internet]. South Dartmouth (MA):, Inc.; 2000-. 



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