Question 1

What is a normal cycle length?

Accepted Answer

Normal cycles range from 21 to 35 days (ACOG guidelines). The average is 28 days, but only 13% of women actually have a 28-day cycle. What matters more than length is consistency — variation of up to 7 days between cycles is considered normal.

Question 2

What causes irregular periods?

Accepted Answer

Common causes include: stress (the #1 cause), PCOS, thyroid disorders, significant weight changes, excessive exercise, hormonal contraceptive changes, perimenopause, and underlying health conditions. If cycles are consistently outside 21-35 days, see your doctor.

Question 3

Is a 35-day cycle normal?

Accepted Answer

Yes! A 35-day cycle is within the normal range (21-35 days per ACOG). Many women naturally have longer cycles. Consistency is more important than exact length — if YOUR cycles are regularly around 35 days, that's YOUR normal.

Question 4

When should I see a doctor about my cycle?

Accepted Answer

See a doctor if: cycles are consistently shorter than 21 days or longer than 35 days, you miss 3+ periods (when not pregnant), cycles vary by more than 9 days month-to-month, or you experience very heavy bleeding.

Question 5

Does an irregular period calculator work for me?

Accepted Answer

Enter your last 3-6 period start dates above to see your cycle variation. If your cycles vary by more than 7 days, a standard period calculator won't work well for you — Cyra's AI handles irregular cycles by learning YOUR unique pattern.

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