What is a Normal Period? Cycle Length, Flow and What’s Healthy & Optimal for You
5 Easy Ways to Track Your Cycle: Normal doesn’t always mean optimal.
By Dr. Cynthia Hall, ND
7 MINUTE READ
Research says a normal menstrual cycle typically occurs every 21-35 days, with bleeding lasting between 3-7 days.
However, what is normal can vary from person to person, and each component of the cycle - length, flow, color and symptoms - gives clues to whether your cycle is optimal for you.
Your Period is a Vital Sign
Your menstrual cycle provides insight into your overall health, including hormone balance, thyroid function, inflammation, nutrient status and metabolic health.
Is My Cycle Normal?
Menstrual cycles (period cycles) are managed by the cyclical nature of, and relationship between, a variety of hormones. Normally, unless we are having troubles conceiving, or transitioning into menopause, we haven’t heard about these hormones since high-school biology class.
They are: Estrogen, Progesterone, Luteinizing Hormone (LH), Follicle Stimulating Hormone (FSH) and Gonadotropin-Releasing Hormone (GnRH).
The relationship between these hormones creates an opportunity for ovulation, uterine lining (endometrial) growth and lining maintenance throughout the menstrual cycle. Each hormone plays an important role in creating an optimal environment for conception (successful meeting of the sperm & egg) and implantation of an embryo.
Do you think you may have underlying inflammation impacting your menstrual cycle and hormones? Check out my other blog that discusses the important link between inflammation and your hormones.
What is Considered a Normal Menstrual Cycle Length?
A 2020 global research study found 77% of its app users in the US and Canada had cycles ranging from 25-31 days. Where Day 1 is the first day of menses (ie. period).
What is Considered Normal Menstrual Cycle Variability?
Each person has a unique cycle, there is variability between cycles, and cycles are affected by various triggers (ex. extreme stress and illness). Despite all of the external factors that affect cycles, they can still be considered normal. Today’s research finds normal cycles are anywhere between 21-35 days.
But, if our cycles shorten or lengthen, are they still optimal? Optimal for fertility? Optimal for hormone balance? Optimal for general health and wellness?
To look further into this topic of ‘optimal’, let us start by digging into the phases of the menstrual cycle first.
The Phases of the Menstrual Cycle
Cycles can be split into two main phases: Phase 1 - Follicular and Phase 2 – Luteal
Let’s start with discussing Phase 2: the Luteal Phase, and how this phase can be connected to shorter cycles.
Phase 2: The Luteal Phase — Is Your Cycle Too Short?
The luteal phase begins after ovulation and ends with the beginning of your next period. The luteal phase begins around day 14 after you ovulate, and ends the day before your next period. The luteal phase is approximately 14 days long.
The key hormone in this phase is progesterone. The dip in progesterone levels at the end of phase 2 send a cue to your body that it is time to have a period, and release the endometrial tissue that has built up (ie. your period).
Top Signs Progesterone May Be Low
Cycles are less than 21-28 days long, or progressively getting shorter
Period Spotting the week prior to a full period. Early spotting is usually a sign that progesterone has dropped too low and too early in the cycle.
Other symptoms that may indicate progesterone levels are not optimal may include: jaw-line acne appearing one week before menses, insomnia and significant mood swings/PMS before menses.
In cases where cycles are longer than 28 days – after confirming you are not pregnant – let’s look at Phase 1: Follicular Phase for some explanation.
Phase 1: The Follicular Phase — Is Your Cycle Too Long?
The Follicular Phase is made up of two parts:
Your period. Normal bleeding duration is between 3-7 days.
Pre-ovulation. Lasting from approximately Day 5 – Day 14 of a 28-day cycle.
The key hormones in this phase are LH and FSH. These hormones are signals sent from your brain to your ovaries for ovulation. Your body needs the right balance and increase of these hormones in Phase 1. This promotes healthy egg development, successful ovulation and appropriate estrogen and progesterone production.
Top Signs LH and FSH are Imbalanced
Cycle length is greater than 31-35 days
Cycle length constantly varies
Ovulation strips do not show positive peaks
You have been diagnosed with PCOS
You have very heavy bleeding
You have large clots in your menstrual blood
5 Easy Ways You Can Start Tracking Your Cycles Today:
There are a few valuable things that you can track during your menstrual cycles to create a better picture of the length of Phase 1 and Phase 2, and your transition between.
The date each menses begins and ends
Note any cramping, pain, amount, clots, color, odor
Presence of spotting (minimal light brown menstrual blood)
Libido (sex drive)
Consistency and amount of cervical mucous (dry, sticky, cottage cheese, egg white, watery)
Other symptoms: headaches, neck aches, insomnia, cravings, acne, bloating, cramping, mood changes
How Can I Find More Information About My Period?
There are tests that provide valuable information as to the root cause of very short or very long periods. Insurance may cover many common hormones that can impact cycles (ex. LH, FSH, Estrogen, Progesterone, TSH). It is important to do these tests on the appropriate day of each Phase in order to get the most accurate and useful information.
Many women in San Diego and across California aren’t sure what a ‘normal’ period looks like so they use other lab tests track a variety of hormones throughout their cycle with multiple readings.
As a Naturopathic Doctor, I order these tests with them and spend time interpreting and explaining the results in detail. These robust tests are paid for out-of-pocket, but provide a more holistic view of hormone trends through your entire cycle. This is very valuable information if you are trying to conceive or going through major life changes (ex. perimenopause and menopause).
If your cycle feels off, you can learn more about the services Dr Hall provides.
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References:
PMID: 232442161, 31482137