Enter your recent cycle lengths to identify hidden patterns and determine your true variance. Know exactly when your irregularity requires medical attention.
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A normal menstrual cycle typically lasts between 21 and 35 days. However, what matters just as much as the length is the consistency. A healthy body operates on a rhythm, and sudden deviations in this rhythm provide insight into your hormonal health.
It is completely normal for your cycle to vary by a few days from month to month. A variation of up to 7, or even 9 days between your shortest and longest cycles over a year can still be considered regular.
The Rule of Thumb: Occasional irregularity is common and usually benign. Consistently unpredictable cycles (differences of 14+ days) or cycles consistently outside the 21-35 day window should be evaluated by a medical professional.
High cortisol (the stress hormone) can inhibit the hypothalamus from releasing hormones that trigger ovulation. Significant weight loss, intense exercise, and poor diet can also stop ovulation entirely.
PCOS is a very common hormonal disorder causing enlarged ovaries with small cysts. It leads to infrequent, prolonged, or unpredictable menstrual cycles due to elevated androgen levels.
Both an underactive thyroid (hypothyroidism) and an overactive thyroid (hyperthyroidism) can cause significant menstrual irregularities. The thyroid gland intimately controls cellular metabolism and impacts estrogen and progesterone.
For women in their late 30s and 40s, hormone levels begin to fluctuate differently as the body transitions toward menopause, often leading to heavier, lighter, or highly irregular cycles.
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