Doctors Say Your Menstrual Cycle Is Your Fifth "Vital Sign"

Lisa Hendrickson-Jack, a certified Fertility Awareness Educator and author of “The Fifth Vital Sign: Master Your Cycles & Optimize Your Fertility,” believes that we as women view our menstrual cycles the way we would shop at a car dealership.

By Gwen Farrell4 min read
shutterstock 1120454918 (1)

“I could get the car with air conditioning, or I could get the car without air conditioning,” she explains. “Or I could get it with heated seats or without heated seats, and it wouldn’t affect engine functioning. And somehow, we think of our ovaries that way. We think that we can turn them on and off with hormonal birth control, or if our cycle stops for whatever reason, we kind of think that it doesn’t affect our regular functioning because we kind of think that our ovarian function and our menstrual cycle is only related to having kids.”

The concept of our menstrual cycle acting as our fifth vital sign is a relatively new one, pioneered by fertility awareness educators and advocates like Hendrickson-Jack. In fact, the concept isn’t all that out there when you consider what vital signs are, and how much hinges on the wellbeing of a healthy, stable cycle. Our cycle is just as insightful into the functioning of our bodies as the other four vital signs, meaning it should rightfully have a place alongside them as an indicator of female health.

What Are Our Vital Signs?

Vital signs evaluate the most basic functions of our body. Traditionally, the four vital signs are blood pressure, pulse rate, respiration (or breathing) rate, and body temperature. Vital signs are normally taken at our annual physicals or in the event of an emergency to measure how well these functions are supporting us, and based on age, gender, weight, and other factors, they can fluctuate accordingly. Essentially, our vital signs can quickly let medical staff (and ourselves) know if something is wrong.

For women, our body temperature can change based on where we are in our cycle, but fundamentally, the average body temperature is usually marked at about 97.8 degrees F. Body temperature is especially important if we’ve developed a fever (a temperature high above average) or even hypothermia (well below what’s been determined normal for us to function). In both situations, temperature can fluctuate to fight off an illness or to indicate that we need medical attention.

Vital signs are important markers for how the key organs that keep us alive are functioning.

Pulse rate measures how many times our heart beats in a minute. An ideal range for adults is anywhere from 60 to 100 beats per minute, though athletes who have particularly strong cardiovascular systems may have a lower rate. Pulse rate not only measures how many times our heart beats, but also the strength of our pulse and any irregular or abnormal heart rhythm. 

Breathing rate evaluates how many breaths we take in a minute, which can increase or decrease according to environment and stress. The average adult takes 12 to 16 breaths in a minute. 

Blood pressure assesses how well our heart contracts and relaxes as blood pushes through its ventricles and valves. As our heart pushes blood into our arteries, blood pressure rises, and it falls as the heart relaxes. High blood pressure can indicate hypertension and other complications, while low blood pressure can indicate hypotension. Normal blood pressure is measured at 120/80.

These four vital signs are important markers for how key organs – our heart and lungs – and their corresponding systems that keep us alive are functioning. 

How Our Cycles Are Indicative of Our Health

As much as we hear from our girlfriends on birth control why it’s nice or “convenient” not to have periods every month, that isn’t the ideal setup for your reproductive system. While many doctors and prescribers are only too happy to suggest getting on birth control to skip our periods, seeing as how the effects are “reversible,” why would we want to suppress a process that's supposed to naturally occur every month? It’s not necessary to have painful periods every cycle, and that’s really where the conversation should end.

Our menstrual cycles, obviously, are inherently tied to our fertility – for better or worse. The no-fuss approach to having periods usually falls back on the logic that if we aren’t trying to conceive, we don’t need a period. But fertility is about so much more than being able to conceive.

Most women’s periods arrive around the average of age 12, signaling that they’ve crossed a milestone when it comes to puberty and development. Given that our first period is the onset of what’s essentially a 40 year journey (up until menopause), our first period is rightfully considered the benchmark for how well we’re developing. When I was 17 and still hadn’t had a period, my doctors were understandably concerned, and this lack of a cycle indicated to me that I was suffering from a hormonal imbalance. Had I found this news out much later instead of in my teens, my future would have looked very different.

A light period with too little blood can indicate an insufficiency in estrogen.

Our period during adolescence and young adulthood can signal to us (and our medical providers) that everything's shipshape and progressing, or that there are suspicious symptoms that need looking into. A light period with too little blood can indicate an insufficiency in estrogen, meaning your uterine lining isn’t producing enough to deliver the thicker quality menstrual blood. Excess pain before and during your period can signal a deficiency in vital nutrients like magnesium or other insufficiencies in your diet. Excess pain can also be indicative of uterine fibroids or conditions like endometriosis. If we’re not experiencing a period, we’re not getting any of the valuable information our body is trying to communicate to us.

The entirety of our cycle offers a fountain of information as well, especially if we’re ovulating or not (a condition called anovulation) in addition to the length and regularity of our cycles and the four individual phases which comprise them. Anovulation especially can indicate a thyroid condition or polycystic ovarian syndrome, as well as being overweight or underweight. Symptoms like spotting before a period or a short luteal phase (the phase following ovulation where our ovaries either prepare for pregnancy or for the onset of another cycle if no fertilized egg is present) can signal other hormonal imbalances such as a luteal phase defect. A luteal phase defect is due to our ovaries failing to produce enough progesterone, which can be a crucial factor in infertility or miscarriage. 

That’s not all. While conditions like polycystic ovarian syndrome are manageable and treatable, PCOS can lead to developing insulin resistance, which in turn can result in type 2 diabetes and cardiovascular disease. Endometriosis, where the uterine lining grows outside the uterus, can trigger inflammation, which can present in skin rashes, abdominal or joint pain, fatigue, and swelling. Issues with our cycle as a whole, if left untreated, can lead to serious, life-altering consequences – which is why it’s so important for us to pay attention to the whole cycle, and not just the “main event” as it were. 

What Your Period Is Trying To Tell You

Your period isn’t a nuisance that should be avoided at all costs, though certain symptoms can make it uncomfortable. If that’s the case, lean into signs – don’t avoid them.

We should view our cycles as the fifth vital sign because everything – our hormones, our thyroid and endocrine system, even our libido – hinges on the functioning of a healthy reproductive system. If our periods are too short, too long, too light or too heavy, we can take these valuable insights as clues into our own health.

Nothing provides such a wealth of insight into the condition of our female health quite like our cycle.

Though a period isn’t necessarily indicative of the occurrence of ovulation, it can help us better enjoy our sex lives on our fertile or non-fertile days, depending on our goals. Our cycle, especially depending on our hormonal needs, can also help us in choosing the best diet and exercise regimen for us, in addition to how much sleep we need each night and our metabolic, emotional, and mental necessities. All of these needs vary from day to day depending on the needs of our cycle, and being literate when it comes to our own bodies keeps us attuned to the specific needs of our health on any given day.

Closing Thoughts

Any woman knows that a medical practitioner will always ask her about the date of her last period during a visit, whether it’s an emergency or not, and that question is truly representative of how we should view our periods as our fifth vital signs.

Our pulse, breathing, blood pressure and temperature are all crucial to our wellbeing – but nothing provides such a wealth of insight and knowledge into the condition of our female health quite like our cycle.

Love Evie? Let us know what you love and what else you want to see from us in the official Evie reader survey.