Menstrual Cycle: What’s Normal, What’s Not

“How do I know if my menstrual cycle is normal?” is a vital question for someone who has only recently experienced menstruation. The word “normal” may mean different things for different women, so it can be a bit hard to explain which things are typical to anticipate.

Before all that, let’s just clear the basics:

What Is a Menstrual Cycle?

Many notable medical journals and websites provide a single-sentence definition of the menstrual cycle as: “The monthly cycle of ovaries changes and uterus lining shedding with the preparation of an egg to fertilize.” These series of changes happen to prepare a woman’s body for pregnancy every month.

How Do I Know What a “Normal” Menstrual Cycle Is 

One thing that many women do not factor in while talking about menstruation is how it varies with age. The periods you experience during the twenties will not be the same in your thirties or forties. 

In your twenties and early thirties, a “normal” menstrual cycle is predictable and regular. By predictable, it means that you can calculate it very easily. An average menstrual cycle lasts anywhere between 24 to 38 days. The mean rests somewhere around 28 days. All these statistics are when you count from the first day of the cycle. These cycle durations can be anywhere between 2 to 7 days. 

In the late 30s to 40s, periods tend to be shorter but with heavy bleeding. During this age range, the predictability falters a bit, and you can also feel changes in the amount of flow. Some cycles may even get skipped, followed by a heavier one. 


What is an “Irregular” Menstrual Cycle?

Here is an easy way to find if your periods are repetitive with the same frequency: identify the last day of your previous cycle till the first day of your next cycle. You have to repeat this for at least three months to be sure. If your period does not fall within the 21 – 35 days range without any reason or if the cycle length exceeds more than 20 days a month, you have an irregular menstrual cycle


 It’s fairly natural to have them once or twice a year, but any more than that and you should immediately seek a doctor’s guidance. 


Main Causes of Irregularities

Sometimes we assume the worst, but there can be a perfectly viable reason for abnormalities in the menstrual cycle. Some of the reasons can be:

  • Pregnancy or breast-feeding
  • Polycystic ovary syndrome (PCOS
  • Pelvic inflammatory disease (PID)
  • Premature ovarian failure
  • Uterine fibroids (noncancerous growths)
  • Eating disorders, extreme weight loss, or excessive exercising

Can I Regulate Abnormal Menstrual Cycles?

Some women say that the use of a birth control pill helps regulate some periods of symptoms. However, if there is an underlying medical condition or an eating disorder that is causing delays, it should be immediately checked. 

As much as we long for an ideal world, some menstrual irregularities cannot be regulated with a pill. 


Menstruation is a natural process, and even though there is a taboo in the society against it, there is nothing inherently “evil” or “bad” about it. It is recommended to use sanitary pads or tampons to absorb the flow. Both these women hygiene products need to be changed on a need-basis, usually every few hours during the heavy days. 

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