Menstruation Length: How Long Does a Period Last? What's normal, what's not

Is your menstruation cycle different from your period length?

Sometimes, it is easy to get confused between your menstruation cycle and your period length. Menstruation is a common phenomenon that happens to most females when they reach their reproductive age and continue till they hit menopause under normal circumstances.

Your menstrual cycle varies from your period length in the sense that your periods are a part of your menstrual cycle.

• Menstrual cycle - The menstrual cycle refers to the number of days that occur between the first day of a period to the first day of the next period. There are four phases in the menstrual cycle, which are menstruation, follicular phase, ovulation and the luteal phase and all of these comprise the entire cycle length.

• Period length - This denotes the number of days you have actual menstrual flow either in the form of bleeding or spotting and marks the menstruation phase of the menstrual cycle.
  
  

What is the normal period length at different stages of life?

Your period length may vary throughout your life starting from your menarche to the time you hit menopause. Under normal circumstances when you do not have any medical condition and you’re not using contraceptives that affect your periods, the following can be your normal period length during the given times:

• Adolescence - When you first begin your period, the phenomenon is termed menarche and the period lengths of different adolescents can vary greatly during this time. Your cycle may be irregular the first few times and on average, the period length varies anywhere from 2 to 7 (or more) days during your adolescent years.

• The early 20s to mid-30s - During this time, your cycle becomes more regular, typically being anywhere between 21 to 45 days in length with a period length varying from 2 to 7 days. Your cycle is fairly regular during this period when you are at your peak fertile years.

• The late 30s and 40s - Even though menopause typically occurs in your 50s, it can happen earlier for some people. But during about 10 years leading up to menopause, your cycle may undergo changes where the cycle length usually shortens with varying number of period days. You may also experience a few missed periods followed by heavy bleeding in subsequent menses. The irregularity further strengthens as you approach perimenopause.
  
  

What is the average period length when you’re on birth control?

If you are on birth control, your period length may become longer or shorter depending on the method of contraception you choose and this is how the different modes affect your period length:

• Hormonal birth control - This constitutes pills, vaginal rings or hormone patches that regulate and control the main reproductive hormones, estrogen and progesterone in your body. The bleeding you experience is known as withdrawal bleeding and occurs in between your hormone doses (either the gap between new strips of pills or new rings and patches). When you use this mode of birth control, your uterine line does not thicken as much and this results in shorter periods with lesser flow. There are even pills that are continuous and result in no periods or bleeding that occurs every three months or even once a year.

• Progestin-only birth control - There are some birth control options that include only the progesterone hormone and come in the form of progestin-only pills (the mini pill), progestin implants or progestin injections (the shot). Bleeding can vary vastly when using this form of contraceptive, with many people facing irregular periods that are shorter, lighter or even absent at times. Sometimes it gets more regular after the first few months, but for many people, their periods stay irregular throughout.

• IUDs - When using hormonal IUDs, your periods can become irregular, light or altogether absent due to the same reason where your endometrium does not thicken as much. On the other hand, with non-hormonal IUDs (the copper IUD), your period length can become longer with heavy bleeding and clots due to vascular changes accompanied by changes in blood flow to the uterus.
  
  

What if your menstrual cycle is irregular?

It can be that you are not using any hormonal birth control but your period length and timing still vary. This is when you have irregular periods that can occur due to a number of medical conditions affecting the length and flow of your period.

Causes of irregularities

There can be many reasons for irregular periods that can include:

• Endometriosis - In endometriosis, the tissue lining the uterine wall grows outside the uterus instead of inside, causing intense menstrual bleeding, cramps and longer periods.

• PCOS - Polycystic ovary syndrome (PCOS) happens when fluid-filled sacs, called cysts, develop on the ovaries due to unclear reasons. It causes an excess of male hormones in the body and affects the ovulation process, resulting in lighter and irregular periods.

• PID - Pelvic inflammatory disease (PID) refers to an infection that occurs in the female reproductive organs from an untreated STD, IUDs or even unhealthy practices like douching. PID can result in heavy bleeding during periods with spotting or bleeding even between your periods.
  
  

When to see a doctor

If you experience irregular periods very frequently with heavier or lighter bleeding, spotting that occurs between your periods and excessive cramps, it is advisable to visit a doctor to get a full diagnosis.