Birth Control

Learn How to Use Your Period as a Vital Sign of Your Reproductive Health

As women, we all know that our period is an extremely important indicator of our health. However, since we're never taught anything beyond the basics of our periods, we can't often learn to gauge our periods. Let's discuss the details on how to read your period!

Ob-gyn doctors and other women's healthcare providers think of your periods as a vital sign, like blood pressure and heart rate. They want to know the number of days between periods, how many days you bleed, how often you change your pads or tampons, whether you have painful periods, and if you have light-headedness or dizziness with your periods. Answers to these questions help clinicians to assess your overall health status.

How do you calculate the number of days between periods?

You count the number of days between the first day of one period to the first day of the next. For example, If the first day of one period starts on the 3rd and your next period starts on the 28th, then these periods are 25 days apart.

How does your period changes over your reproductive lifespan?

Your first period as a teen can occur as early as 8 years of age. The average age is 12-13 years. By 15 years of age, 98% of women will have had their first period. Breast development precedes your first period by 2-3 years. By the third year after the first period, 60-80% of menstrual cycles are 21-34 days long which is similar to a young adult woman.

The duration of normal menstrual flow is generally 5 days but can last for up to 8 days. Most blood loss occurs within the first 3 days. The length of your menstrual cycle remains relatively constant throughout the reproductive years, but cycle length varies as a woman approaches menopause.

As women approach menopause, they may not ovulate regularly. Perimenopausal women may have periods 35 days apart or greater which is normal. The average age of menopause in the United States is 51 years.

What is a "regular" range of days between periods?

When you are not on hormonal birth control (These are called ovulatory menstrual cycles.), periods are not like clockwork - the days between periods may vary. During the first year, 90% of periods are 21-45 days apart. By the third year after the first period, 60-80% of menstrual cycles are 21-34 days long which is similar to a young adult woman.

Doctors consider a range of periods that are 21-34 days apart "regular". For example, if over a 6 month span your periods are 21, 25, 22, 27, 32, and 28 days apart, the number of days between your periods are "regular". The length of the cycle can vary by a few days each month.You may think that the inconsistent number of days between periods is irregular because you cannot plan as well and your periods may affect your plans, the clothes that you wear, your performance at a competitive sports, lively arts, or special event. Even though your periods may come at inconvenient, even embarrassing times, a range between 21-34 days is regular.

Is skipping periods on hormonal contraceptives safe?

Hormonal contraceptives can help regulate your periods so you have your periods at a predictable time each month, every 3 months, or not at all!

Women often ask if skipping periods on combination (containing estrogen and progestin) hormonal contraceptives is safe. The short answer is "yes". A longer answer involves the mechanism of action of combination hormonal contraceptives. These medications act to prevent pregnancy by preventing ovulation and by thickening the cervical mucus. They also keep the innermost lining of the uterus called the endometrium very thin. When you have a period, you actually are shedding the top part of the endometrium. If your endometrium is very thin, you'll have either a light period or no period at all.

Is skipping periods when I am not on hormonal contraceptives safe?

Most women who are not on hormonal birth control who are skipping periods because they are not ovulating monthly develop thickened endometrium. Over time, reproductive aged women, excluding women in the perimenopause, who routinely have periods that are far apart have an increased risk of developing endometrial cancer because they are not shedding their endometrial lining. When these women do have periods, periods tend to be heavy because they have more endometrium to shed.

Are painful periods normal?

Painful periods are common. Painful periods can be a symptom of a localized prostaglandin excess or a condition called endometriosis.

Pain during periods or dysmenorrhea is the most common menstrual symptom among adolescent girls and young women. Painful periods usually start within 6-12 months of the first period.

Pain caused by prostaglandins make the uterus contract and can cause intense cramping and discomfort. Prostaglandins are hormones that your body naturally produces.

Painful periods or dysmenorrhea can also be caused by endometriosis. Endometriosis is a pathological condition where the endometrial tissue (tissue that usually lines the innermost part of the uterus) is found in other parts of the body, most commonly around the ovaries, fallopian tubes, rectum, and bladder. Endometriosis is a diagnosis made at surgery.

How can I treat painful periods?

You do not have to suffer in pain and miss school or work or your disrupt your normal daily activities. Here are some things that you can do for treating painful periods and your overall well being:

  • Exercise (at least 30 minutes a day five days a week)
  • Get plenty of sleep (7-10 hours per night)
  • Practice relaxation techniques like deep breathing, meditation, yoga

Your clinician may recommend the following medications:

  • Pain relievers such as non-steroidal anti-inflammatory drugs (NSAIDS) like naproxen or ibuprofen
  • Hormonal medications, such as birth control pills, vaginal ring, or patch with the option to take each type continuously to suppress periods
  • A mix if the above medication types

If medications do not relieve pain within 3-6 months, the next step is finding and treating the cause of your dysmenorrhea. You may need surgery.

NSAIDs work best if taken at the first sign of your menstrual period or pain and on a schedule so pain does not recur. You usually take them for only 1 - 2 days. Women with one or more of the following should not take NSAIDS:

  • bleeding disorders
  • asthma
  • aspirin allergy
  • liver damage
  • stomach disorders
  • ulcers

When should I seek help?

The American College of Obstetrics and Gynecology recommends that you should consider an evaluation if you have any of the following:


  • Menstrual periods that have not started within 3 years of breast development have not started menstrual periods by 14 years of age with signs of male pattern hair growth on the face, chest or nipples
  • Have not started menstrual periods by 14 years of age with a history or examination suggestive of excessive exercise or eating disorder
  • Have not started by 15 years of age
  • Occur 90 days apart even for one cycle

All Reproductive Aged Women

  • Occur more frequently than every 21 days or less frequently than every 45 days
  • Last more than 7 days
  • Require frequent pad or tampon changes (soaking more than one every 1-2 hours)
  • Are heavy and are associated with a history of excessive bruising or bleeding or a family history of a bleeding disorder
  • Have bleeding in between periods

Talk to a Doctor About Your Period

If you're experiencing anything unusual with your period, make sure to speak to a doctor. It can seem like quite an effort to go to the doctor just to discuss your period, but remember, your period is just like a vital sign - and talking to a doctor could make a huge difference in your reproductive health.

If you can't go to a physical doctor, Alpha physicians are available to help talk you through your symptoms and figure out if you need further care or a specific treatment plan. If your treatment plan can be prescribed online, we'll help you do so. If your case requires further consideration, then we will refer you to a doctor in your area.

Our medical team is here for you.

Get the customized prescription treatment you need - online, right now.

Get Started