12 Surprising Reasons For Irregular Periods

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It is part of a woman’s reproductive system and occurs every month in response to reproductive hormones including estrogen and progesterone.

But why periods? because it is necessary to start the reproductive system in females and connect the steps of becoming a mother.

Periods are considered irregular when they do not come in the normal range, mean -periods that occur less than 21 days or more than 35 days (1).

Research estimate that each woman experiences menstruation 400 times in her fertility age.

However, talk to your doctor if you experience frequent irregular periods, from month to month, and it is not that harmful.

But irregular or heavy bleeding can lead to iron deficiency due to low blood count, which also leads to low haemoglobin.

NOTE: Also, Irregular bleeding and spotting are almost permanent after 1 to 3 months of treatment (2).

1. Birth Control Pills

The most commonly given pill is the combined hormonal pill including estrogen and progesterone.

Progesterone is the hormone that prevents pregnancy, and the estrogen component controls menstrual bleeding (3).

See, birth control pills do not directly affect periods, but they can create some problems, which lead to irregular periods including:

  • Dietary changes
  • Exercises
  • Continuous birth control pill
  • Stress, affect both mental and physical health (4)

Birth control pills also face some adverse effects such as – nausea, headache, cramps, breast tenderness, increased vaginal discharge, and low libido.

These pills are mainly used to prevent cramps, excessive bleeding, etc but excessive use leads to irregular periods (5)

2. Pregnancy

Yes, pregnancy can lead to irregular periods, and can also make it difficult in being pregnant, but how?

If women skip periods, they may also have months where they do not ovulate (Which is a process in which a mature egg is released from the ovary)

Basically, during irregular periods, women also lose their 2 vital hormones called estrogen and progesterone, which are responsible for being pregnant.

NOTE: Overall, an irregular menstrual cycle causes subtle or sufficient hormonal imbalance.

Common signs of pregnancy, but these signs may also see in other health conditions, so confirm it with the doctor, which includes:

  • Vomiting
  • nausea
  • feeling of tiredness
  • giddiness
  • feel lazy and sleepy

Check Out – Ideal Exercises During Pregnancy

3. Stress

A study on female college students showed stress levels were associated with an irregular menstrual cycle and menstrual disorders.

NOTE: Physical stress also leads to irregular periods such as extreme exercises.

A study conducted were 696 women aged 20–40 years says, that an irregular menstrual cycle was associated with high chronic stress levels (7).

Mental stress also facilitates corticotrophin (affects our response to stress) hormone, which activates the nervous system and can lead to menstrual problems (8) (9).

Check Out – Is Music Can Treat Mental and Physical Illness

4. Perimenopause

Perimenopause starts as early as 40 years and may continue for 8 to 10 years, before menopause, where estrogen level is gradually decreased.

A menstrual calendar study of Danish women showed that, when women entered the menopause transition, an irregular period cycle occurred (10).

Which was allied with increased variability in the duration of bleeding (11).

The most common signs and symptoms of premature menopause include:

  • Irregular periods
  • hot flashes
  • night sweat
  • joints pain
  • longer period or short period
  • mood swings
  • dryness in the vagina, eyes, and mouth
  • Increase or decrease in weight
  • heavy bleeding
  • depression, and anxiety
  • headache
  • breast tenderness
  • hair loss or thinning
  • disturbance on sleep
  • Period stopping altogether without any other reason
  • heavy bleeding

To prevent perimenopause adopting a healthy lifestyle includes – avoiding smoking, and alcohol, doing regular exercise, with a healthy diet, maintaining BMI, etc

Check Out – Menopause: What Is It? Age, Duration, Signs, Treatment.

5. Uncontrolled Diabetes

An irregular menstrual cycle may also be associated with type II diabetes, and cardiovascular diseases (12).

The majority of studies reveal increased spreading of diabetes type II and cardiovascular in women with irregular cycles (13).

There are many studies, research, and doctors who considered that diabetes is associated with an irregular period cycle.

When someone has diabetes, their body’s ability to produce insulin is completely stopped, which can lead to Hypoglycemia.

  • Hypoglycemia is a condition, where a diabetes person’s blood sugar level falls too low.
  • Insulin is a hormone made in our pancreas, which helps the body to maintain body sugar levels.

Some common symptoms of diabetes such as:

  • Increased hunger
  • Blurry vision
  • Weakness
  • Frequent urination
  • More thirsty than usual days

Check Out – Natural Ways To Prevent Pre-Diabetes And Diabetes

6. Excessive Exercise

Studies have shown that high-intensity exercise is allied with menstrual dysfunction and subfertility among high-performance female athletes.

Evidence support that excessive exercise is allied with periods dysfunction and subfertility among high-performance female athletes.

Excessive exercise has been shown in oligomenorrhea and other menstrual dysfunctions, and amenorrhea (missing one or more period cycles)

Amenorrhea” can also lead to underlying medical conditions such as:

  • Low bone density, which causes osteoarthritis, more the chance of bone fracture
  • Slow metabolism
  • Muscles easily break down
  • Decreased appetite, which leads to weight loss

7. Smoking

In a 2018 study where smokers had a 1.4 times higher prevalence of irregular menstrual cycles than non-smokers.

In addition, Smoking and high cigarette intake were significantly associated with premature menopause based on data (15).

Smoking generates over 4 to 5 thousand chemicals when burned, the best known of which is – nicotine.

Nicotine also causes increased oxidative stress, neuronal apoptosis, DNA damage, and reactive oxygen species increase.

In addition, irregular periods were defined as having more than 7 days of variability in the length of the cycle (9).

8. Certain Foods

Research conducted by high school girls from Mashhad, the values of salty–fatty foods, fast foods, and caffeine work the same as smoking.

In addition, certain eating disorders are related to irregularities and periods of amenorrhea (16) (17)

Also, a shortage of calcium and non-saturated fatty acids is associated with painful menstrual periods (18)

9. Obesity and underweight

According to a report in 2020, more than 2 billion adults (39% of the adult global population) were overweight.

A study conducted on 1095 women (18-25 years old) in Taiwan reveals that higher BMI women are at higher risk of irregular periods, compare to 18.5–23.9 women (19).

Research has shown reported that obese women had more irregular and longer menstrual cycles (20) (21)

Obesity (excessive fat content) can increase the production of estrogen, which in turn into overweight, which is also allied with menstrual disorders (22).

The research found that women who are underweight have heavy menstrual bleeding, compared to women with normal weight.

Researchers have shown that having heavy menstrual blood loss in underweight women was, compared to normal-weight women.

Check Out – Obesity, And Pregnancy, Is Any Relation B/W Them, Risk

10. Certain medicines

Studies report that women (age 20 to 29 years old) used more medicines, of course, due to periods issues, compare to men.

Here are some common medicine, which may interact with irregular periods include:

  • Blood-thinning
  • Olanzapine is used to treat schizophrenia
  • Haloperidol is used to treat mental issues (23)
  • Thyroid medicines
  • Chemotherapy drugs

A study showed that consumption of toluene, cyclohexane, and benzene (found in certain medicines) may cause irregular periods.

Another report suggests that antipsychotics have more side effects in menstrual irregularities, compared to atypical (24) (25).

If you notice any discomfort, and frequent periods, after taking any medication then meet with your doctor (26).

Talk to a doctor, before taking any medicine, whether it is supplemented, or herbs, because it may interact with your condition.

11. Females Issues

Here are some common female issues, that are related to or can trigger an irregular periods cycle which includes:

Primary ovarian insufficiency (POI)

Ovarian insufficiency is referred to as ovarian failure.

Research shows a frequent loss of blood for about 3 months, in both healthy and non-pregnant women, to be considered to check for POI diagnosis.

POI is not a mild condition, it is estimated that around 0.3 to 1.1% of reproductive-age women face premature menopause (27).


Irregular menstrual cycles may be a sign of chronic conditions such as diabetes, and polycystic ovary syndrome (PCOS) (28) (29).

A 2016 study reported that women with irregular menstrual cycles had over a two-fold increase in ovarian cancer risk.

Other common women’s health issues

  • Asherman’s syndrome
  • Hormone-containing intrauterine devices (IUDs)

12. Adrenal gland Disorder

The AGP the hormone, which controls heart rate, boosts metabolism, immunity, and reduces HBP, and stress, which is located on top of the kidney.

The endocrine system plays a key role in the being rhythm of the menstrual cycle setting (30) (31)

During a study, the period cycle pattern also shows the innate endocrine health environment and irregular menstrual cycles (32).


But long and frequent menstrual cycle leads to low hemoglobin, also iron deficiency, due to loss of blood.

Irregular periods main reason is an unhealthy lifestyle, stress, and not doing any physical activity, even in young females.

Talk to your doctor, if you see any irregularity in your periods, whether it is fast, slow, or heavy, basically, it is not a serious issue.


Hello, I'm Sahil bisht, I am a Mechanical engineer, As well as, aspiring blogger with an obsession for health. This blog delicate to people who want to learn in health.

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