Our Health Library information does not replace the advice of a doctor. Please be advised that this information is made available to assist our patients to learn more about their health. Our providers may not see and/or treat all topics found herein.
Missed or Irregular Periods
Menstrual periods often occur every 21 to 35 days. But you may be different. Missed or irregular periods must be looked at in terms of what is normal for you.
Menstrual periods often aren't regular during the first few years after your period starts. It may take several years for the hormones that control menstruation to reach a balance.
Pregnancy is the most common cause of a missed period. If you might be pregnant, treat yourself as if you are pregnant until you know for sure. Use a home pregnancy test as the first step to find out if you are pregnant.
If you aren't pregnant, other causes of missed or irregular periods include:
- Excessive weight loss or gain. Low body weight is a common cause of missed or irregular periods. Obesity also can cause menstrual problems.
- Eating disorders, such as anorexia or bulimia.
- Increased exercise. Missed periods are common in endurance athletes.
- Emotional stress.
- Chronic diseases, such as diabetes or irritable bowel syndrome.
- Medicines such as birth control methods. These may cause lighter, less frequent, more frequent, or skipped periods or no periods at all.
- Hormone problems, such as polycystic ovary syndrome. They may cause a change in the levels of the hormones that the body needs to support menstruation.
- Illegal drug use.
- Problems with the pelvic organs, such as an imperforate hymen or Asherman's syndrome.
- Breastfeeding. Regular periods may not resume until after you have finished breastfeeding.
- Primary ovarian insufficiency. This means you stop having periods before age 40. It can be caused by surgery, chemotherapy, or radiation therapy to the belly or pelvis.
Remember, you can still become pregnant even though you don't have periods. Practice birth control if you don't wish to become pregnant.
If you've skipped a period, try not to worry. It isn't uncommon to miss periods now and then. Unless you're pregnant, your cycle likely will return to normal next month.
Check Your Symptoms
The medical assessment of symptoms is based on the body parts you have.
- If you are transgender or nonbinary, choose the sex that matches the body parts (such as ovaries, testes, prostate, breasts, penis, or vagina) you now have in the area where you are having symptoms.
- If your symptoms aren’t related to those organs, you can choose the gender you identify with.
- If you have some organs of both sexes, you may need to go through this triage tool twice (once as "male" and once as "female"). This will make sure that the tool asks the right questions for you.
Many things can affect how your body responds to a symptom and what kind of care you may need. These include:
- Your age. Babies and older adults tend to get sicker quicker.
- Your overall health. If you have a condition such as diabetes, HIV, cancer, or heart disease, you may need to pay closer attention to certain symptoms and seek care sooner.
- Medicines you take. Certain medicines, such as blood thinners (anticoagulants), medicines that suppress the immune system like steroids or chemotherapy, herbal remedies, or supplements can cause symptoms or make them worse.
- Recent health events, such as surgery or injury. These kinds of events can cause symptoms afterwards or make them more serious.
- Your health habits and lifestyle, such as eating and exercise habits, smoking, alcohol or drug use, sexual history, and travel.
Try Home Treatment
You have answered all the questions. Based on your answers, you may be able to take care of this problem at home.
- Try home treatment to relieve the symptoms.
- Call your doctor if symptoms get worse or you have any concerns (for example, if symptoms are not getting better as you would expect). You may need care sooner.
Pain in adults and older children
- Severe pain (8 to 10): The pain is so bad that you can't stand it for more than a few hours, can't sleep, and can't do anything else except focus on the pain.
- Moderate pain (5 to 7): The pain is bad enough to disrupt your normal activities and your sleep, but you can tolerate it for hours or days. Moderate can also mean pain that comes and goes even if it's severe when it's there.
- Mild pain (1 to 4): You notice the pain, but it is not bad enough to disrupt your sleep or activities.
Shock is a life-threatening condition that may quickly occur after a sudden illness or injury.
Adults and older children often have several symptoms of shock. These include:
- Passing out (losing consciousness).
- Feeling very dizzy or lightheaded, like you may pass out.
- Feeling very weak or having trouble standing.
- Not feeling alert or able to think clearly. You may be confused, restless, fearful, or unable to respond to questions.
Many prescription and nonprescription medicines can affect the menstrual cycle. A few examples are:
- Aspirin and other medicines (called blood thinners) that prevent blood clots.
- Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen (for example, Advil or Motrin) and naproxen (for example, Aleve).
- Hormonal forms of birth control, such as birth control pills, Depo-Provera injections, Implanon or Nexplanon implants, and the levonorgestrel IUD (Mirena).
- Hormone therapy.
- Medicines used to treat cancer (chemotherapy).
- Thyroid medicines.
Seek Care Today
Based on your answers, you may need care soon. The problem probably will not get better without medical care.
- Call your doctor today to discuss the symptoms and arrange for care.
- If you cannot reach your doctor or you don't have one, seek care today.
- If it is evening, watch the symptoms and seek care in the morning.
- If the symptoms get worse, seek care sooner.
Seek Care Now
Based on your answers, you may need care right away. The problem is likely to get worse without medical care.
- Call your doctor now to discuss the symptoms and arrange for care.
- If you cannot reach your doctor or you don't have one, seek care in the next hour.
- You do not need to call an ambulance unless:
- You cannot travel safely either by driving yourself or by having someone else drive you.
- You are in an area where heavy traffic or other problems may slow you down.
Make an Appointment
Based on your answers, the problem may not improve without medical care.
- Make an appointment to see your doctor in the next 1 to 2 weeks.
- If appropriate, try home treatment while you are waiting for the appointment.
- If symptoms get worse or you have any concerns, call your doctor. You may need care sooner.
Call 911 Now
Based on your answers, you need emergency care.
Call 911 or other emergency services now.
Sometimes people don't want to call 911. They may think that their symptoms aren't serious or that they can just get someone else to drive them. Or they might be concerned about the cost. But based on your answers, the safest and quickest way for you to get the care you need is to call 911 for medical transport to the hospital.
Here are some ways to care for yourself when you have missed or irregular periods:
- Eat a balanced diet. Being underweight or overweight can cause missed and irregular periods.
- If you are an endurance athlete, you may have to cut back on your training or increase your calorie intake. Stress and low body fat are thought to contribute to missed or irregular periods in athletes. Be sure to talk with your doctor about hormone and calcium supplements to protect against bone loss if you are missing periods.
If you think you might be pregnant
Do a home pregnancy test if you've had sex since your last period. If the result is positive, practice the following good health habits until you see your doctor:
- Eat a balanced diet.
- Don't smoke or use other tobacco products.
- Don't use alcohol or drugs.
- Avoid caffeine, such as coffee, tea, or chocolate. Or limit your intake to about 1 cup of coffee or tea each day.
- To avoid the risk of toxoplasmosis, don't clean a cat litter box.
- Avoid people who are ill.
- Take a vitamin supplement that contains folic acid. Or take a prenatal vitamin.
If the home pregnancy test is negative but you still have pregnancy symptoms, it's a good idea to see your doctor to confirm the results. Practice good health habits until you see your doctor.
When to call for help during self-care
Call a doctor if any of the following occur during self-care at home:
- Early symptoms of pregnancy, such as:
- Missed periods.
- Increased urination.
- Breast tenderness or enlargement.
- Nausea and vomiting.
- Two or more menstrual periods are missed in a row.
Preparing For Your Appointment
You can help your doctor diagnose and treat your condition by being prepared for your appointment.
Current as of: April 19, 2023
Author: Healthwise Staff
Clinical Review Board: All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.
To learn more about Healthwise, visit Healthwise.org.
© 1995-2023 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.