Key takeaways:
Menstrual cycles last from 21 to 35 days. You may notice changes in your menstrual cycle length over your lifetime.
Pregnancy is only one reason you might miss a period. Some other causes of missed periods include perimenopause, health conditions, stress, and overexercising.
Seek medical care if you miss more than one period in a row or miss two in a year.
If you’re sexually active and trying to avoid getting pregnant, missing your period can make you anxious. A missed period can be the first sign of pregnancy. But there are many other reasons why you can miss a period. (Still, it’s a good idea to take a pregnancy test if you miss a period and there’s a chance you might be pregnant.)
Let's take a closer look at some of the other causes for missing a period, and what you can do to get your periods back on track.
Can you miss your period and not be pregnant?
Missing your period doesn’t always mean you’re pregnant. Some people miss a period now and then. And a small percentage of people have what’s called amenorrhea. That’s when you miss your period for 3 months in a row.
Your period is part of the menstrual cycle, which is regulated by your hormones. Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) prepare and release an egg from your ovary. And estrogen and progesterone prepare your uterus for a potential pregnancy. These hormones are controlled by a brain-body connection called the hypothalamic-pituitary-ovarian (HPO) axis.
A number of factors can affect that HPO axis and lead to missed periods. These include:
Having an energy deficit (eating too few calories or burning too many)
Weight loss or gain
Perimenopause
Certain medical conditions
Stress
What can cause you to miss your period besides pregnancy?
There are a range of factors and medical conditions that can affect the HPO axis — and lead to missed periods. Here are eight reasons you can miss your period if you’re not pregnant.
1. Energy deficit
If you don’t absorb enough calories to meet your energy needs, it can cause an energy deficit. This means that your body is running on less energy than it needs. Having an energy deficit may lead to what’s called functional hypothalamic amenorrhea. This is one of the most common causes of missed periods.
Some things that can trigger functional hypothalamic amenorrhea include:
Very low-calorie diets
Disordered eating, particularly anorexia
Exercising a lot and not replenishing the calories you burned
Some illnesses that affect food absorption, like inflammatory bowel disease or celiac disease
2. Too much exercise
If you exercise for long periods of time, it can be hard to replenish all the calories you burn during your workouts. If you’re not consuming enough calories, it can trigger hypothalamic amenorrhea. Athletes — like long-distance runners, dancers, and gymnasts — may experience this phenomenon.
If you exercise a lot and don’t get your next period for 45 days or haven’t had it for 3 months, you may have functional hypothalamic amenorrhea. You may want to talk to a healthcare professional like an obstetrician-gynecologist (OB-GYN). They can work with you to figure out how many calories you need to eat to support your physical activity. This can help bring back your period.
3. Polycystic ovary syndrome (PCOS)
Polycystic ovary syndrome (PCOS) is a medical condition caused by hormone changes. Females with PCOS may have high levels of hormones called androgens, which can cause a range of symptoms.
One of the main symptoms of PCOS is having irregular or missed periods. Often, people with PCOS will have fewer than eight periods a year.
Other signs that you might have PCOS include:
Weight gain
Excess body and facial hair
Severe acne
Darkening of the skin folds
Talk with your healthcare team if you think you have symptoms of PCOS. There’s treatment for PCOS, including hormonal birth control, which can help stabilize your hormones. This may make your periods more predictable.
4. Obesity
Obesity is defined as having a body mass index (BMI) of 30 or higher. If you’ve been told you have obesity, your body may be producing too much insulin and androgens. These hormonal changes are similar to those in people with PCOS, and they can lead to missed periods.
If you’re in this weight category, talk with your primary care provider or OB-GYN about what you can do to help restore your period.
5. Stress
Many people have some stress in their lives. But sometimes stress is intense, or it can last a long time. When you experience stress, your body releases cortisol from the adrenal gland. This is part of the fight-or-flight response.
High cortisol levels affect the HPO axis, which regulates your menstrual cycle. This may cause you to miss your period.
It can be hard to know if stress is causing a missed period. If you had a recent stressful event, or if you have ongoing stress in your life, it could be a factor. Talk with your primary care provider or your OB-GYN to make sure other factors aren’t also affecting your period.
To help reduce the effects of chronic stress, you can try stress-management techniques, like deep breathing and meditation. It may be helpful to talk to a mental health professional as well. They can help you better understand what’s causing your stress and work with you to develop ways to reduce and manage it.
6. Perimenopause
Perimenopause is when your estrogen levels start to decline. It’s the period of time leading up to menopause. Perimenopause typically starts in your mid- to late-40s, and it often lasts about 4 to 8 years.
During this period of time, your hormone levels can fluctuate. Some months, you may have normal periods. And other months, you may miss a period altogether. Or you can have several missed periods in a row.
7. Hormonal birth control
Some people may choose to or need to skip periods. This is called “menstrual suppression.” There are several ways you can use hormonal birth control to skip periods.
But, even if you’re not trying to suppress your period, hormonal birth control may cause changes to your menstrual cycle. For example, if you switch from one hormonal birth control method to another, it can make your periods lighter or irregular. If you’ve recently started on birth control or changed types, it may take a few months for your period to become regular again.
8. Thyroid problems
The thyroid gland is a butterfly-shaped gland in the front of the neck. Hormones produced by the thyroid control metabolism and body temperature. They also play a role in regulating your menstrual cycle.
When your body produces too much thyroid hormone, it’s called hyperthyroidism. And when it produces too little, that’s hypothyroidism. Both conditions can cause irregular or missed periods.
Menstrual cycle length
Your menstrual cycle is the amount of time between the first day of one period and the first day of the next one. Not everyone’s menstrual cycle is the same length. A menstrual cycle can range from 21 days to longer than 35 days. The average menstrual cycle lasts 28 days.
Your HPO axis determines the length of your menstrual cycle. The first half of the menstrual cycle is called the follicular phase. It can last anywhere from 14 to 21 days. The second half of the menstrual cycle is called the luteal phase, which lasts about 12 days for most people. This is why menstrual cycle lengths vary from person to person.
But you might also be surprised to hear that your menstrual cycle length can change over time. Your menstrual cycle starts out long during the teen years when you first get your period. Your cycle gets progressively shorter after you hit your mid 20s until you reach your mid 40s. For most people, menstrual cycles are at their most consistent during their 30s. Your cycles get longer again around your mid-40s as you reach perimenopause.
But health conditions, stress, and other factors reviewed above can all impact the normal progression of your menstrual cycle.
How long of a delay between periods is normal?
A “late period” is a delay of 5 or more days between periods. This means that your menstrual cycle is 5 days longer than normal. This can be completely normal because your menstrual cycle length can change over time. Studies show that it can be normal for a person’s menstrual cycle to change by several days over a lifetime. In one study, nearly half of women reported a 7-day difference between their shortest and longer menstrual cycles over the course of a year.
When your period hasn’t occurred at all, even after the next one is due, it’s considered a missed period. It can be normal to miss a period from time to time. But you shouldn’t miss more than one period in a row if you’re not pregnant. Seek medical care if you miss more than one period in a row.
Can you induce your period?
Prescription hormonal medications can induce periods. Some people claim certain things can kick start a period, like:
Exercise
Supplements
Sex
Orgasms
But there’s no real evidence that these things actually work.
When should you seek care about a missed period?
You should see your primary care provider or an OB-GYN if you experience any of the following issues with your period:
You miss more than one period in a row or miss two in a year.
You’ve had regular periods that have a predictable number of days between periods, but your period has become less predictable.
You have periods, but they stop and then they come back.
You have unusually heavy bleeding.
You have too-frequent periods (cycles lasting 21 days or fewer).
You experience bleeding between periods.
Your periods are very painful.
Your OB-GYN or primary care provider can help determine if a medical condition or other issue is leading to these symptoms.
How long after a missed period should you take a pregnancy test?
It’s a good idea to take a pregnancy test if you miss a period and you’ve been sexually active. Home pregnancy tests are very reliable. They measure the amount of a pregnancy hormone, called human chorionic gonadotropin (hCG), in your urine.
You can take a pregnancy test as soon as 1 day after a missed period, depending on what brand of test you use. But results may not be as accurate then. It can take up to a week after a missed period for the levels of hCG to be high enough to be detected on most brands. So, you may need to take a second pregnancy test 3 to 5 days after the first test if you still don’t get your period.
Frequently asked questions
Your menstrual cycle length can change over time. So, it can be normal for your period to be delayed for 5 to 7 days if you’re not pregnant.
No, a urinary tract infection (UTI) won’t cause a missed period. A UTI affects your urinary system, not your reproductive system.
A severe UTI can increase your stress hormones (cortisol). High cortisol levels can sometimes lengthen your menstrual cycle. So, it’s possible to have a late period during or after a UTI.
Yes, you can take a home pregnancy test before you miss a period. Some home pregnancy test brands can measure very low levels of human chorionic gonadotropin (hCG). These tests may be able to pick up hCG levels as early as 4 to 6 days before your expected period.
Keep in mind that you may need to take a second pregnancy test to confirm your results if your period is late. HCG levels rise every day during early pregnancy, so your pregnancy test result will be more accurate after your period is due.
Your menstrual cycle length can change over time. So, it can be normal for your period to be delayed for 5 to 7 days if you’re not pregnant.
No, a urinary tract infection (UTI) won’t cause a missed period. A UTI affects your urinary system, not your reproductive system.
A severe UTI can increase your stress hormones (cortisol). High cortisol levels can sometimes lengthen your menstrual cycle. So, it’s possible to have a late period during or after a UTI.
Yes, you can take a home pregnancy test before you miss a period. Some home pregnancy test brands can measure very low levels of human chorionic gonadotropin (hCG). These tests may be able to pick up hCG levels as early as 4 to 6 days before your expected period.
Keep in mind that you may need to take a second pregnancy test to confirm your results if your period is late. HCG levels rise every day during early pregnancy, so your pregnancy test result will be more accurate after your period is due.
The bottom line
If you miss your period, but aren’t pregnant, something else may be causing the missed periods. A range of factors can lead to hormonal imbalances that can interrupt your menstrual cycles. These include your energy balance, levels of exercise, stress, your age, and certain health conditions.
Missing a period occasionally isn’t usually something to worry about. But if you miss your period more than once in a while or twice in a row, it’s important to seek medical care. Your healthcare team can help diagnose any underlying causes and work with you to get your periods back on track.
Why trust our experts?
References
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