top of page

What's a 'Normal' Menstrual Cycle?

Updated: Nov 29, 2023

One of the most common things I hear in practice after describing the menstrual cycle to women is “I had no idea that’s how that worked" or "Wow, I didn't realize that what I'm experiencing isn't normal". I want to break it down so that you can learn more about what wasn't taught to you in sex-ed and what you thought was maybe common, but not necessarily normal.

We’ll start from the beginning.

A woman’s menstrual cycle is regulated by several hormones: estrogen, progesterone, luteinizing hormone (LH), and follicle stimulating hormone (FSH). The menstrual cycle can be divided into 3 phases: the follicular/proliferative cycle, ovulation, and the luteal/secretory phase.

Menstrual cycle with ovarian changes including folliculogenesis, ovulation from the ovary, corpus luteum secreting progesterone and estradiol. Follicular phase, ovulation, and luteal phase are all depicted with changes in E2, progesterone, LH, FSH and the endometrium
This shows the entire menstrual cycle. The ovarian changes are noted at the top into 3 phases. Beneath that, shows the development of the follicle, ovulation, and release of hormones from the corpus luteum. You can see the fluctuations in hormones below.

The Follicular Phase- the start of your menstrual cycle!

Day 1 of the menstrual cycle is marked by the first day of bleeding. This also marks the beginning of the follicular phase which persists until ovulation. During this time, body temperatures are lower and the development of ovarian follicles begins. Folliculogenesis (or development of the follicles) begins the last few days of the preceding menstrual cycle until the release of the mature follicle at ovulation.

💡Women begin puberty with around 400,000 follicles!

The development of the follicles occurs in several stages. Multiple follicles develop at once, and by day 8 of the cycle, the body recognizes the “strongest” follicle and promotes more growth of that follicle while suppressing growth of the other follicles. This “strong” follicle will eventually develop into the egg released at ovulation. In women with PCOS, these follicles may stay enlarged and turn into ‘polycystic ovaries’.

An ovary going through folliculogenesis during the follicular phase, ovulation during ovulatory phase, and corpus luteum which produces progesterone during the luteal or proliferative phase. This all takes places during the menstrual cycle.

During this phase, estrogen increases to parallel the growth of the follicle. Granulosa cells exist within the ovary and help to produce hormones. On these cells, there are receptor sites for Follicle Stimulating Hormone or FSH. As FSH is released from the pituitary gland (in our brain) it stimulates conversion of androgens on the granulosa cells, to estrogen. With a dramatic rise in estrogen, the brain releases Luteinizing Hormone (LH) from the anterior pituitary gland. The LH surge occurs around 12-36 hours prior to ovulation. Ovulation occurs around 10-12 hours after a peak in LH.


If you’re trying to have a baby- this is when you want to have sex! During ovulation, libido increases, and men find women more attractive. This study went as far as to have men sniff “dirty t-shirts” and determined that they found that women are most attractive when they are ovulating.

You may also notice an increase in cervical mucus (vaginal discharge). This mucus helps move sperm into the cervix so that it can meet the egg. Women can track this throughout the month to determine when their most 'fertile' window is. If you want to get pregnant, have sex at this time. If you don't want to get pregnant, avoid sex at this time.

Luteal Phase

This phase is dominated by progesterone and is typically 14 days long. Following ovulation, the remaining cells that are not released at ovulation become enlarged. These cells form the corpus luteum. The corpus luteum is a transient (short lived) endocrine organ that secretes progesterone.

menses, proliferative, secretory stages of menstrual cycle depicted by uterus ovary, ovum and the uterine and ovarian cycle during the menstrual cycle.

This is why the second half of the cycle is dominated by progesterone! The purpose of this is to prepare the previously “estrogen primed” endometrium for implantation of a fertilized egg. There will be a rise in progesterone about 3-5 days after ovulation of around day 19-21 of the cycle. Estrogen will also slightly increase at this time. Corpus luteum function declines by the end of this phase if implantation does not occur and all hormone levels will drop. This drop in hormones signals menses to occur and the endometrial lining is shed.

Some women may notice cramps, breast tenderness, fatigue, swelling/bloating, acne and cravings at this point in the cycle. Mild symptoms are normal, but if they become extremely bothersome, require constant painkillers, interact with your daily function, or cause you to be extremely depressed/anxious, there may be some type of hormonal imbalance.

What's 'Normal'?

The average length of a cycle is 28 days, but can range from 25-30 days. The average woman will bleed from 4-7 days. The typical amount of blood lost during menstruation is 60 mL. Anything heavier than 80ml or bleeding longer than 7 days is called menorrhagia. Anything less than 30mL or bleeding less than 4 days is hypomenorrhea.

It's hard to imagine how much blood that is, so to give you an idea- a fully saturated super tampon/pad holds up to 12mL. A fully saturated regular pad/tampon holds about 5mL. A fully saturated light tampon/pad holds up to 3mL. You can also use menstrual cups to track blood loss.

Keep in mind, this isn't an exact method, but can give you and idea as to what is normal and what might be too heavy/light. This may also vary slightly from period to period.

What do I do?

If you feel as if your period is irregular or abnormal, there are other options outside of hormonal birth control. Determining what the root cause of the issue is can not only improve your reproductive health now, but for years down the road as well.

Testing can always help see what is happening with your hormones and can also check you for any underlying thyroid issues that may be causing this, possible anemias from excessive blood loss and can look to see if you are dealing with a reproductive disorder like PCOS or endometriosis.

Birth control and medications are not your only options when it comes to reproductive and hormonal health. There are other avenues that you can pursue to help your overall health. If you do need surgery or medications, there are lifestyle modifications and supportive supplements that can continue to improve your quality of life.


Work With Me 👇

If you are looking for natural ways to regulate or improve your menstrual cycle, decrease your PMS, or address any other reproductive disorders, you can click here to sign up with a complimentary 15 minute phone call with me. We can discuss your goals at that time and determine whether or not we will be a good fit for each other. We will discuss necessary nutrients, dietary options, as well as lifestyle and exercise programs catered to YOU specifically to help you reach your health goals.

Dr. Katie Zaremba natural fertility doctor

About Dr. Zaremba

Dr. Zaremba received her bachelor's degree from Western Michigan University in Biomedical Sciences and minored in Chemistry and Psychology. She completed her doctoral training at Palmer College of Chiropractic. During her time in school, she took post-doctoral training through The Clinic on Disease and Internal Disorders (CDID) earning her a Diplomate from the American Board of Chiropractic Internists (DABCI).


This web site offers health, wellness, fitness and nutritional information and is provided for informational purposes only. This information is not intended as a substitute for the advice provided by your physician or other healthcare professional. You should not rely on this information as a substitute for, nor does it replace, professional medical advice, diagnosis, or treatment, Always speak with your physician or other healthcare professional before taking any medication or nutritional, herbal or homeopathic supplement, or using any treatment for a health problem. If you have or suspect that you have a medical problem, contact your health care provider promptly. Do not disregard professional medical advice or delay in seeking professional advice because of something you have read on this web site. The use of any information provided on this web site is solely at your own risk. Nothing stated or posted on this web site or available through any services offered by Dr. Katie Zaremba DC, Dr. Katie Zaremba LLC, are intended to be, and must not be taken to be, the practice of medicine. Information provided on this web site DOES NOT create a doctor-patient relationship between you and any doctor affiliated with our web site. Information and statements regarding dietary supplements have not been evaluated by the Food and Drug Administration and are not intended to diagnose, treat, cure, or prevent any disease.


bottom of page