5 things you should know about your cycle

The average adolescent girl will be affected by menstruation for 3,000 days in her lifetime. That works out to more than eight years (Compassion Canada, 2018). And that’s just your menstrual cycle (ie the time that a women is bleeding). But what about the rest of the cycle?

The unfortunate reality for many girls and women is that most do not understand the basics of a normal healthy cycle. In this discussion we will be covering what a “normal” period looks and feels like, the importance of the cervix, the hormones that govern the hypothalamic–pituitary–gonadal axis (HPG axis), laboratoryevaluation of the hormonal cycle, and monitoring techniques using basal body temperature (BBT) and cervical mucous changes. There are some excellent resources that can be found at the end of this discussion too.

Let’s start with day 1 of your cycle, the first day of flow…

1. Menstruation: length, blood loss and pain

Normal menstruation length is 3-7 days (4-5 days is average). Normal blood loss is 25-60 ml (50 ml is average). Heavy menstrual bleeding is defined as blood loss greater than 80 ml or lasting for more than seven days.

Menstruation should occur virtually symptom free. Most women feel bloating or a heavy sensation. A little bit of cramping on day one is considered normal. Current evidence suggests that normal period pain is prostaglandin-mediated. As your uterine lining starts to break down at the end of your cycle, it releases prostaglandins. These hormone-like chemicals have two effects on the myometrium (the smooth muscle tissue of the uterus) – uterine contraction and decreased blood flow. This causes cramping and inflammation. Prostaglandins are a normal part of the process, but too many can cause pain.”Increased prostaglandins, specifically PgF2-alpha and PgE2, cause uterine contractions that lead to ischemia and pain… Studies have found that women with dysmenorrhea produce 8 to 13 times more PgF than do women without dysmenorrhea.” Women’s Encyclopedia of Natural Medicine, Tori Hudson, 2008

Severe period pain is throbbing, burning, searing, or stabbing. It lasts for many days and can occur between periods. Severe period pain also doesn’t improve with NSAIDs, and it interferes with your daily activities. These are signs of secondary dysmenorrhea, defined as menstrual pain resulting from pelvic pathology, as is seen in women with endometriosis or adenomyosis.

2. The cervix: a biologic valve that controls the access of sperm and microorganisms into the uterine cavity

Your cervix has a very important protective mechanism. It keeps the vaginal flora separate from the uterus, which is a sterile environment. It also retains the fetus; therefore, it must be competent (ie strong enough to hold baby, fluids, and extra embryonic tissue).

Within it are crypts. The intricate system of crypts in the cervix is lined with secretory cells that produce 20-60 mg of mucous daily, containing water, electrolytes, and mucins (mucins are responsible for changing the consistency of cervical fluid). Vaginal mucous changes due to hormones are used to track ovulation and fertility for a woman who wants to track her cycle. See the resources at the end of this post for more information about tracking.

3. Hormonal players: GnRH, LH, FSH, Estrogen, Progesterone (there are others, but these are the main players)

  1. GnRH: Gonadotropin-releasing hormone
  2. LH: Luteinizing hormone
  3. FSH: Follicle-stimulating hormone

Side note: cholesterol serves as a precursor for the production of estrogen and progesterone. Women who do not consume adequate cholesterol in their diets will have issues with the production of all steroid (sex) hormones, leading to hormonal deficiency patterns.

The following discussion pertains to a menstrual cycle where the egg is not fertilized by a sperm. If it is not fertilized, the egg dissolves away and is shed along with the uterine lining during menstruation. This is a basic overview of the communication between brain and ovaries, known as the hypothalamic–pituitary–gonadal axis (HPG axis).

Brain: Two glands are involved, the hypothalamus and the pituitary.

GnRH from the hypothalamus tells the pituitary to release 2 hormones, LH and FSH, which speak to the ovaries to produce estradiol and progesterone.

Side note: GnRH is affected by sleep, stress, and obesity; therefore, it is crucial that you sleep well, manage stress, and maintain a healthy weight for optimal hormone signalling. The importance of stress”A disruption in the messages between the hypothalamus (which produces gonadotropin- releasing hormones) and the anterior pituitary (which releases FSH and LH, follicle-stimulating and luteinizing hormones) brings about a mis- timing of the release of these hormones and a subsequent lack of ovulation and/or estrogen and progesterone production by the ovaries. The timing of the release of these pituitary hormones, as well as of estrogen and progesterone, is what determines a normal, regular menstrual cycle. This timing can be adversely affected by stress, and by the same token, the timing can be improved by stress reduction.” Women’s Encyclopedia of Natural Medicine, Tori Hudson, 2008

Further discussion of the hormonal players requires a visual representation of your entire cycle, starting from day 1 which is menses (first day of flow, not spotting), and marks the onset of the follicular phase of the menstrual cycle.

The follicular phase is the period of recruitment of multiple follicles (the blue circles within the yellow circles in the image below) and emergence and growth of one dominant follicle. Around day 7, all of the follicles stop growing and begin to degenerate except for one. During this phase, rising levels of estradiol (green line) are associated with thickening (proliferative phase) of the endometrium (the lining of the uterus depicted in pinkish-red along the bottom of the image). Those follicles are secreting estradiol into the blood, telling the anterior or front part of the pituitary to secrete LH. Eventually, the one dominant follicle secretes a large amount of estrogen into the blood stream, which tells the pituitary gland to release a huge surge of LH into the blood stream. In a 28-day menstrual cycle, this is occurring around day 12. You can also see how LH spikes in the middle of the cycle (between the follicular and luteal phase). That occurs right before ovulation.

The luteal phase, which begins on the day after the LH surge, is characterized by the formation of the corpus luteum (yellow circle with bursting purple follicle). The corpus luteum is a hormone secreting structure. It secretes progesterone and estradiol to prime the uterus for implantation (secretory phase). In the absence of pregnancy, the corpus luteum declines (yellow fluffy clouds in image), therefore hormone secretion declines, resulting in the endometrium losing its blood supply. It is then shed, which is the beginning of menstruation.

Source: Hall, J.E. 2019. Yen and Jaffe’s Reproductive Endocrinology, 8th Edition. Physiology, Pathophysiology, and Clinical Management; Chapter 7 – Neuroendocrine Control of the Menstrual Cycle, Pages 149-166.e5. Available online 22 February 2018.

If you are a visual learner, I highly recommend watching this video as a review.

4. Lab work-up/hormonal lab reports: blood vs saliva (the pros & the cons)

Evaluation of the hormonal cycle using blood draws will ideally take place on two days, day 3 and day 21. Day 3 hormone testing includes Estrogen, LH, FSH, Prolactin, and Testosterone. Progesterone is tested on day 21. Please note that depending on your cycle length, these days may be different for you.

A lot of information can be obtained from this workup; however, it has its limitations.

Serum (blood) testing

Pros: Very standardized, and often covered by insurance.

Cons: May miss the intended measurement if your cycle is off (ie you have a longer or shorter cycle), may not get the entire picture (because it is a single time point in your cycle), requires multiple blood draws (on days 3 and 21), and the potential stress of a blood draw.

Another option is salivary hormone testing, which requires the collection of saliva samples over the course of a woman’s cycle. By correlating self-reported symptoms with hormone levels throughout the menstrual cycle, it is often possible to identify hormone imbalances underlying a symptom or issue. 

Salivary testing

Pros: Painless, easy to do at home, relatively inexpensive, and plots the entire cycle so trends can be observed.

Cons: Not as reliable for FSH and LH, and can be inconvenient for the patient (month long hormone assessment requires spitting into 11 tubes over 33 days). More information can be found here. No matter what method of testing you choose, always discuss results with a qualified healthcare practitioner. If your medical doctor is not familiar with salivary hormone testing, then seek the services of a qualified naturopathic doctor. Ideally, your medical doctor and naturopathic doctor should collaborate and communicate with each other in the interest of providing you with the best possible care.

5. Symptothermic monitoring: Basal body temperature (BBT), cervical mucous, and cervical position

This type of monitoring is not only low cost (you may have to buy a BBT thermometer), but more importantly, it helps you learn about your cycle and your body and how it changes throughout your cycle. Not to mention no blood draws or spitting into tubes, if that’s a concern. For women trying to conceive, these methods also improve timing attempts and can even uncover causes of infertility!

Side note: PDF downloadable charts for tracking can be found in the resources section below. Tracking for several months may be required for a full picture. I recommend at least 6 months, especially if your cycles are irregular or if using these methods to track ovulation.

A few tips for BBT tracking: oral (mouth) temperature is taken upon waking, so take your temperature at the same time each day (weekends too!) Your temperature should increase with increasing progesterone levels. Do not expect huge temperature shifts with this. The temperature shifts are subtle, but when graphed, should reveal a distinct pattern, both pre and post ovulation. BBT tracking can tell you a lot about your cycle, but it is NOT a good predictor of ovulation since the temperature shifts after ovulation. But it can tell you if ovulation is occurring. Take home point: BBT tracking is not a good predictor for ovulation.

Cervical mucous: mucous changes throughout a cycle are normal and healthy. Fertile mucous is like egg whites; rich in water, inorganic salts, and mucin, which forms a gel that keeps the cervical canal open. This change in consistency allows sperm to move up through the cervix into the uterine cavity with little effort, meaning it actively assists sperm in getting up to the cervix to the egg to get fertilized. Fertile mucous lasts approximately 3-5 days (can be 1 day), is stretchy, discharged in copious amounts (women will report feeling wet), and forms a symmetrical circular spot on underwear. Infertile mucous on the other hand can be dry, watery, milky, sticky, or crumbly.

Cervical position: Most women are not comfortable checking their cervical position, so I will not discuss that here. However, that information can be found in Toni Weschler’s book Taking Charge of your Fertility: The Definitive Guide to Natural Birth Control, Pregnancy Achievement, and Reproductive Health.

It is important to work with a doctor who can guide you through this process and encourages you to be proactive with your health. Symptothermic monitoring in combination with appropriate laboratory testing and a thorough health history will provide the most complete picture of your hormonal cycle.


Symptothermic monitoring charts.

Book Taking Charge of your Fertility: The Definitive Guide to Natural Birth Control, Pregnancy Achievement, and Reproductive Health.

Period tracker App: there are many, but I recommend Clue.

Phendo is an app that allows women with endometriosis to track their symptoms, treatments and self-management strategies.

Video on ovulation.