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Cycle health

How the menstrual cycle works, what is normal, and when patterns warrant attention.

cycle health

Your Cycle Is a Vital Sign: What Length, Variability & Flow Tell a Clinician

ACOG calls the menstrual cycle a vital sign. Here's how to read your own cycle data the way a clinician would — what counts as normal, what to flag, and what to bring to your next appointment.

Apr 18, 2026 · medically reviewed

cycle health

Hypothalamic Amenorrhea: Why Your Period Disappeared

Hypothalamic amenorrhea causes missing periods through energy deficit, over-exercise, or stress. Learn how it differs from PCOS, how recovery works, and what it means for fertility.

Apr 2, 2026 · medically reviewed

cycle health

Postpartum Period Return: When Cycles Come Back After Birth

When your period returns after birth, how breastfeeding delays it, the LAM method's actual effectiveness, and when to be concerned about postpartum bleeding patterns.

Mar 17, 2026 · medically reviewed

cycle health

Perimenopause Cycle Changes: STRAW+10 Staging in Plain English

What happens to your cycle from age 35 onward, the STRAW+10 staging system, hormonal changes in perimenopause, and when irregular is normal vs concerning.

Mar 8, 2026 · medically reviewed

cycle health

Stress and Missed Periods: When It Is Actually Stress

Stress can delay or cancel ovulation through HPA axis suppression of GnRH. Here is when stress explains a missed period and when something else is going on.

Feb 19, 2026 · medically reviewed

cycle health

Thyroid and Menstrual Cycles: When and How to Test

Hypothyroidism and hyperthyroidism both shift menstrual cycles. Here is how each one changes your pattern, when to ask for a TSH, and what the labs mean.

Feb 14, 2026 · medically reviewed

cycle health

Endometriosis and Your Cycle: What Patterns to Notice Early

Heavy painful periods are not normal. Endometriosis takes 7 to 10 years to diagnose on average. Here are the cycle patterns and red flags that should prompt earlier evaluation.

Feb 9, 2026 · medically reviewed

cycle health

Secondary Amenorrhea: Why Your Periods Stopped and What to Investigate

Workup for periods that stopped after being normal: pregnancy first, then PCOS, hypothalamic, thyroid, prolactin, and POI. When to refer.

Jan 27, 2026 · medically reviewed

cycle health

Heavy Menstrual Bleeding: When It Is HMB and What to Do

Defining heavy menstrual bleeding with PBAC and product soak-through, iron-deficiency screening, and the evidence-based evaluation pathway.

Jan 25, 2026 · medically reviewed