Your menstrual cycle is the time between the first day of your last period and the first day of your next period. Most menstrual cycles are 24 to 38 days. When you have a cycle that’s less than 24 days, you might be experiencing an early period.
The first time you get your period as a teenager is called menarche. This usually happens between the ages of 10 and 16. The average age to get your first period is 12.4 years. When you first start having a period, it can be normal for your cycles to be irregular.
You may go several months between periods or get your period sooner than expected. This isn’t usually a health concern, and your cycle will get more regular within a year or two.
Perimenopause is the period of transition between regular menstruation and menopause, when you stop having periods altogether. Most people experience perimenopause in their 40s and enter menopause in their 50s. During perimenopause, it’s common to have irregular periods.
You may have periods that come more often than usual (short cycles) or much less often than usual (long cycles). You may bleed between periods, have lighter periods, or have heavier periods.
If menstruation is bothering you during perimenopause, speak to your healthcare provider for treatment options, which may include hormonal medications, lifestyle adjustments, or treatments of underlying medical conditions.
Your thyroid is a small, butterfly-shaped organ found on your neck. It releases thyroid hormones. These hormones help regulate many of your body’s systems, including your reproductive system, which impacts your periods.
When you have too much thyroid hormone (hyperthyroidism) or not enough thyroid hormone (hypothyroidism), your periods may become irregular. You may notice fatigue, digestive issues, increased anxiety or depression, trouble sleeping, or other symptoms. The specific symptoms will depend on the type of thyroid condition you have.
Experiencing severe or long-term stress can impact your period, causing it to be irregular or absent. This may happen because stress can disrupt certain hormones, including those that affect the reproductive system. More research is needed. It’s unclear how much stress or what type of stress is most likely to cause irregular periods.
Some research shows women with anxiety or depression are more likely to have shorter or irregular cycles, as well as more severe premenstrual syndrome (PMS) symptoms.
Very strenuous exercise can lead to irregular or absent periods. This usually occurs when regular, intense exercise is combined with low body weight or when you lose weight too quickly.
Reduce the intensity or duration of your workouts if you are experiencing irregular or absent periods due to excessive exercise. Make sure to eat a balanced diet and get adequate calories when exercising intensely. It’s especially important to get enough calcium and vitamin D, as these nutrients help support reproductive hormones and regular menstrual cycles.
Sometimes, the medications you are taking may cause your period to be irregular or come early. Most commonly, this happens from hormonal birth control, such as birth control pills, implants, or injections. IUDs that contain hormones can also change your period by making it lighter or absent.
Other medications that can cause irregular periods include medications to treat epilepsy (seizures) or medications for mental health issues. If you think a medication you are taking is causing irregular periods, talk to your healthcare provider.
Polycystic ovary syndrome (PCOS) is a condition affecting female reproductive organs that can cause irregular or missed periods. It’s characterized by an imbalance of hormones and increased levels of male hormones (androgens).
Besides irregular periods, you may experience unwanted hair growth on your face, metabolic symptoms, and infertility. If you have symptoms of PCOS, it’s important to visit your healthcare provider for treatment options.
Primary ovarian insufficiency (POI) is when you stop ovulating (releasing eggs) before the age of 40. This can cause difficulties getting pregnant, as well as irregular periods, hot flashes, and night sweats. POI is rare, affecting 1-2% of menstruating people under the age of 40. The condition requires a diagnosis by a healthcare provider.
The pituitary gland is a small gland at the base of the brain that secretes several hormones that help regulate body systems. Conditions affecting your pituitary gland can cause hormone imbalances in your body, some of which can impact your periods.
For example, if you have a prolactin-secreting pituitary tumor, your body will secrete too much of the hormone prolactin, which can cause you to have irregular or absent periods. Pituitary issues are often treatable with medication or surgery, but require a diagnosis by a healthcare provider.
Endometriosis is a condition in which uterine-like tissue grows outside of the uterus on other nearby organs. Endometriosis affects about 10% of people who have periods. It can cause very painful periods, infertility, heavy periods, painful sex, pelvic pain, and pain while peeing or pooping.
Endometriosis can also cause bleeding between periods, which may make you think you are having an early period. If you have signs of endometriosis, you should visit your healthcare provider for a diagnosis and treatment plan.
If you are experiencing irregular periods, it can be helpful to track your periods and symptoms for a few months. This can help you understand what is going on with your body during your cycles.
After tracking your period, you may find that you aren’t experiencing irregular periods, but rather your normal period length falls at the earlier or later end of a normal cycle. Remember, a normal cycle can last anywhere from 24 to 38 days.
Tracking your cycle may also tell you that your periods are irregular most of the time. Tracking will also help you determine what other symptoms you’re experiencing throughout your cycle. This information can be helpful when you talk to your healthcare provider.
You can track your cycle by hand in a calendar or notebook. You can also use a cycle tracking app or a computer program. What you record depends on your needs, but helpful information to track includes:
- The date your period starts
- The date your period ends
- Each day you bleed, noting how heavy or light the bleeding is
- Period-related symptoms during the month, such as mood changes, cramps, backaches, headaches, and food cravings
- Vaginal discharge changes
Most people will have an early or irregular period on occasion, and 14-25% of people who menstruate experience irregular periods on an ongoing basis. This can include periods that come early, late, or not at all.
Having one or two irregular cycles or periods that seem to come early or late is usually not a health concern, especially if your cycle returns to normal the next month. If you have several irregular periods in a row, it may be time to visit a healthcare provider.
You may also want to see your provider if your irregular periods are accompanied by very painful cramps, trouble getting pregnant, unusually heavy or light bleeding, or other symptoms you are concerned about.
If you visit your healthcare provider for period concerns, they may:
- Ask about your cycle lengths, dates, and symptoms
- Perform a pelvic exam to check the health of your reproductive organs
- Use imaging tests like ultrasounds to get images of your uterus and nearby organs
- Have your blood tested for various conditions and abnormalities
There are many reasons why a period might come early, including puberty, perimenopause, PCOS, excessive exercise or stress, medications you’re taking, or underlying conditions that affect your hormones.
It’s normal to have an early period from time to time. However, if you are frequently experiencing early or irregular periods, it’s best to visit a healthcare provider for guidance and treatment.
