What Your Menstrual Cycle Says About Your Overall Health: Learning to Read It as a Fifth Vital Sign

In 2015, the American College of Obstetricians and Gynecologists published a statement declaring that the menstrual cycle should be considered the fifth vital sign—alongside temperature, blood pressure, pulse, and respiratory rate. Not as a symbol of fertility, but as a direct indicator of a woman’s overall health. What happens in your body each month isn’t noise. It’s information.

What a healthy cycle looks like—and why it matters to know it
A healthy menstrual cycle lasts between 21 and 35 days. Bleeding lasts between 3 and 7 days, with a moderate to heavy flow in the first days. The color ranges from bright red to dark red. Pain, if present, is mild and manageable without strong medication. Understanding what’s normal—and what isn’t—is the first step toward no longer normalizing suffering.

The four phases—and what each one reveals

Menstrual phase: large clots may indicate progesterone deficiency or endometriosis. Very light flow may signal low estrogen levels.

Follicular phase: if you consistently feel exhausted or experience brain fog during this phase, it may be a sign that estrogen isn’t rising as it should.

Ovulation: if there’s no ovulation, there’s no progesterone—and without it, the cycle becomes a hormonal roller coaster.

Luteal phase: severe premenstrual syndrome—intense irritability, anxiety, significant bloating, or migraines—is not normal, even if it’s common. It may signal progesterone deficiency or systemic inflammation and deserves medical attention, not tolerance.

What your cycle can reveal beyond reproduction

Thyroid health: hypothyroidism can alter the cycle in characteristic ways before other symptoms appear.
Iron levels: heavy bleeding can lead to iron-deficiency anemia, showing up as fatigue and dizziness.
Systemic inflammation: severe menstrual pain may be a sign of endometriosis—a condition that takes, on average, 7 to 10 years to be diagnosed because the pain is normalized.
Chronic stress: it can suppress ovulation or even stop the cycle altogether.

How to start reading your cycle
Track the first day of each cycle, the duration of bleeding, flow, color, presence of clots, pain level, and overall mood in each phase. After three cycles of tracking, patterns will begin to emerge—patterns you may have never noticed before.

Apps like Clue, Natural Cycles, or Flo allow you to log all this data and generate reports you can bring directly to your medical appointments.

Breaking the silence as an act of health
In many Latino families, the menstrual cycle has long been treated as a private, almost secret topic. That silence has a real cost on women’s health. Conditions like endometriosis and polycystic ovary syndrome are often diagnosed late, in part because women don’t know what to ask.

Your cycle speaks to you every month.
Learning its language is learning the most basic—and most powerful—language of your own body