⏰ Why Is My Period Late? — Period Delay Calculator

Formula

Expected next period = Last period date + Cycle length

Days late = Today - Expected next period (if positive)

Pregnancy

The most common reason for a missed period in sexually active women of reproductive age. Take a home pregnancy test if your period is more than a few days late.

Stress

High stress levels can affect your hypothalamus, the part of your brain responsible for regulating hormones that control your menstrual cycle. This can delay or prevent ovulation, making your period late.

Significant Weight Changes

Both extreme weight loss and weight gain can cause hormonal changes that affect your menstrual cycle. Very low body weight can stop ovulation entirely.

PCOS (Polycystic Ovary Syndrome)

PCOS causes irregular periods or absent periods due to hormonal imbalances. If you frequently have cycles longer than 35 days or very irregular cycles, consult your doctor about PCOS screening.

Hormonal Birth Control

Starting, stopping, or changing birth control can cause temporary irregularities. Some forms of birth control (like certain IUDs or implants) can stop periods entirely.

Excessive Exercise

Intense athletic training, especially combined with low body weight, can disrupt hormones and cause missed or late periods.

Thyroid Issues

Both overactive (hyperthyroidism) and underactive (hypothyroidism) thyroid conditions can cause irregular periods. A simple blood test can check your thyroid function.

• Best timing: The first day of your missed period or later
• Early detection tests: Can detect pregnancy 5-6 days before your missed period
• Morning testing: Use your first morning urine for highest accuracy (most concentrated hCG)
• If negative: Retest in 3-5 days if your period still hasn't arrived

• Your period is more than 90 days late (amenorrhea)
• You have severe pelvic pain or cramping
• You experience heavy bleeding or bleeding between periods
• You have three or more missed periods in a row
• Your cycles are consistently irregular (varying by more than 7-9 days)
• You have symptoms of PCOS, thyroid issues, or other hormonal disorders
• You're trying to conceive and have concerns about ovulation

How many days late is normal for a period?

A period can be up to 7 days late without being a major cause for concern, especially if you usually have irregular cycles. However, if you're sexually active, consider taking a pregnancy test if your period is more than a few days late.

How many days late should I take a pregnancy test?

Most pregnancy tests are accurate from the first day of your missed period. Early detection tests can work 5-6 days before your expected period, but for best results, wait until your period is at least 1 day late.

Can stress delay your period?

Yes! Stress is one of the most common causes of a late period. Chronic stress can disrupt the hormones that regulate your menstrual cycle, potentially delaying ovulation and, consequently, your period.

My period is 10 days late but pregnancy test is negative. What should I do?

If you tested early, you might have gotten a false negative. Wait 3-5 more days and retest with your first morning urine. If still negative and your period hasn't arrived, see your doctor to rule out other causes like PCOS, thyroid issues, or stress.

What's the difference between a late period and a missed period?

A late period is one that arrives after your expected date but within a reasonable timeframe (usually within 7 days). A missed period typically means your period is more than 7-10 days late or doesn't arrive at all during a cycle.

Can you have a late period and not be pregnant?

Absolutely! While pregnancy is a common cause, there are many other reasons for a late period including stress, weight changes, travel, illness, hormonal birth control, PCOS, thyroid issues, and perimenopause.

Does being late on your period mean you're pregnant?

Not necessarily. A late period can have many causes. However, if you're sexually active and your period is late, pregnancy is a possibility and worth testing for.

How long can stress delay your period?

Stress can delay your period by several days to weeks. In extreme cases, chronic stress can cause amenorrhea (absence of periods). Once stress is reduced, your cycle typically returns to normal within 1-2 months.

Can birth control make your period late?

Yes. Starting, stopping, or changing hormonal birth control can cause temporary irregularities. Some forms (like IUDs or implants) may cause very light periods or stop them entirely, which is usually normal.

When should I worry about a late period?

See a doctor if your period is more than 90 days late, if you have three or more consecutive missed periods, if you experience severe pain or heavy bleeding, or if late periods are accompanied by other concerning symptoms.

Can exercise delay your period?

Yes, especially intense exercise or sudden increases in athletic training. The combination of high-intensity workouts and low body fat can disrupt hormones and delay or stop periods.

What is the longest a period can be late without being pregnant?

While there's no absolute limit, periods delayed beyond 90 days (amenorrhea) should be evaluated by a doctor even if pregnancy tests are negative. This could indicate hormonal imbalances, PCOS, thyroid issues, or other conditions.