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Why is my period late?
The common reasons a period is late, from stress and illness to PCOS, thyroid and pregnancy, when to take a test and when to see a doctor.
Updated
In short
Why is my period late?
A period is usually called late when it hasn't started five or more days after you expected it. The most common reasons are pregnancy, stress, illness, travel, changes in weight or exercise, breastfeeding, hormonal birth control, PCOS and thyroid problems. If there's any chance you're pregnant, take a test. If you miss three periods in a row, see a doctor.
Written by the Gyne team · Medical review: pending
Key takeaways
- If you could be pregnant, take a pregnancy test first.
- Stress, illness and travel can delay ovulation, which delays your period.
- Conditions like PCOS and thyroid problems often cause irregular or missed periods.
- See a doctor if you miss three periods in a row, or sooner if something worries you.
Could I be pregnant?
Pregnancy is the first thing to rule out if you've had sex. Home pregnancy tests are most reliable from the first day of your missed period. If the result is negative but your period still hasn't come, test again in a few days.
What else can make a period late?
Your period comes about two weeks after ovulation. Anything that delays ovulation delays your period. Common causes include:
- Stress, which can affect the hormones that control ovulation.
- Illness, like a cold, flu or another infection.
- Travel and changes in time zone or routine.
- Losing or gaining weight quickly, or eating too little.
- Hard exercise, especially with low energy intake.
- Breastfeeding, which can pause periods.
- Hormonal birth control, or stopping it.
- Polycystic ovary syndrome (PCOS).
- Thyroid problems.
- Perimenopause, the years before periods stop.
How late is too late?
Cycles naturally vary by a few days. One late period is common and usually nothing to worry about. Missing periods for three months in a row, when you're not pregnant, is called amenorrhea and should be checked by a doctor.
When to see a doctor
- You've missed three periods in a row and you're not pregnant.
- You have a positive pregnancy test with severe belly pain, shoulder pain, dizziness or bleeding: get care right away.
- Your periods have become irregular when they used to be regular.
- You also have new acne, extra hair growth, hair loss, or feel very tired or cold all the time.
- You're 15 or older and haven't had a period yet.
How Gyne helps
When your period is late, Gyne doesn't just flash a warning. It asks about stress, illness, travel or a test, moves your prediction to fit, and explains the change in one line, with what to do next.
PeriodsThis guide is general information, not medical advice. Only a doctor can diagnose a condition.