Irregular Periods: Causes, Complications, Treatment, Pregnancy, and More

You’re experiencing irregular periods if your menstrual cycle length keeps increasing or decreasing and your periods are either too early or too late.

While slight variation in the gap between your periods from month to month is considered normal, it could also be indicative of an underlying health issue. 

There are several factors that can affect the regularity of your menstrual cycle. Here, we have compiled information to help you learn about irregular periods, their causes and treatment, and how to try for a baby when your cycle is irregular. 

What are irregular periods?

Also known as oligomenorrhea, irregular periods refer to: 

• Missed periods

• Delayed periods 

• Erratic periods 

• Abnormal bleeding patterns

While 28 days is considered the average menstrual cycle length, this can be shorter or longer by a few days. However, you’re having irregular periods if your menstrual cycle: 

• Is shorter than 24 days

• Is longer than 38 days 

• Varies drastically from month to month

After puberty, several women’s menstrual cycle regularizes with a similar periodicity. However, it is completely normal for the cycle to vary by a few days from month to month.

Common causes of irregular periods

Irregular periods (oligomenorrhea) can occur due to various reasons, often related to hormonal changes. The main hormones that regulate the menstrual cycle are progesterone, estrogen, and follicle-stimulating hormone. If there is a change in the rise and fall of these hormones, it can cause irregular periods.

While irregular periods are common and not necessarily a cause for concern, long-term irregularity could indicate an underlying health condition.

Watch this explainer video for Doctor Pooja Mittal’s expert advice on the causes of irregular periods.

Natural, non-disease-related causes of irregular periods

Some natural and non-disease-related causes of irregular periods are as follows:

• Natural hormonal changes: These changes delay the beginning of your period and postpone its start date.

• Puberty: Irregular periods could start from the first year of puberty and last for a year or two.

• History of irregular periods: If you have a family history of irregular menstruation, you could experience it, too.

• Perimenopause: This period before menopause could last as long as 10 years and cause irregular periods. Two missed periods often indicate the start of late perimenopause.

• Start of menopause: This usually occurs between the age of 45 and 55 and marks the end of your menstrual cycles.

• Stress and anxiety: Both chronic and short-term anxiety can adversely affect your hormone balance, causing irregular periods.

• Endurance or excessive exercise: Doing endurance or aerobics exercises or over-exercising can affect your menstrual cycle and cause irregular periods.

• Extreme weight loss: Whether because of extreme dieting, an eating disorder, or an illness, extreme weight loss can lead to irregular periods. 

• Extreme weight gain: This can also disrupt the regularity of your menstrual cycle and cause irregular bleeding.

• Hormonal birth control: Birth control such as contraceptive pills and intrauterine devices (IUDs) can also cause irregular periods.

• Smoking and alcohol consumption: Smoking cigarettes can shorten your menstrual cycle. Alcohol can also change your menstrual cycle and stop ovulation. 

• Medication side effects: Some medications can cause irregular periods as a side effect.

Medical conditions that can cause irregular periods

Some of the health conditions that can cause irregular periods are as follows:

• Polycystic ovary syndrome (PCOS): This hormonal disorder afflicts reproductive-age women and causes: 

  • Irregular periods that are infrequent or prolonged 

  • Excessive levels of androgen, the male hormone 

  • Failure to ovulate regularly 

• Thyroid or pituitary disorders: The following disorders can cause irregular periods:

  • Hypothyroidism: When the thyroid gland produces low levels of the thyroid hormone

  • Hyperthyroidism: When the thyroid gland produces an excessive amount of the thyroid hormone

  • Hyperprolactinemia: When the pituitary gland produces too much prolactin

• Pelvic inflammatory disease (PID): Usually the result of a sexually transmitted disease, this causes the female reproductive system to get inflamed.

Pregnancy-related causes of irregular periods

Some of the pregnancy-related causes of irregular periods are as follows: 

• Exclusive breastfeeding of your newborn: This can cause amenorrhea or the absence of menstruation, as you are not likely to ovulate for the next six months or so. 

• Postpartum bleeding: There is also a gap between postpartum bleeding and your first regular period post-delivery. Learn more here.

• Miscarriage or pregnancy loss: This can cause irregular periods. It may take a few months for your periods to regularize again.

While these are some causes of irregular periods, if you are worried about your menstrual cycle is irregular, reach out to your Doctor or Gynecologist for guidance.

Other conditions related to irregular periods

Irregular periods could also be a symptom of one of the following health conditions:

• Hormone-secreting tumors are abnormal growths that form in your pituitary gland  

• Type 1 diabetes, in which the pancreas either produces little or no insulin

• Primary ovarian insufficiency occurs when an under-40 woman’s ovaries stop functioning normally

• Congenital adrenal hyperplasia is a set of genetic disorders affecting the adrenal glands

• Cushing’s syndrome, which occurs when the cortisol hormone level is abnormally high

• Infertility or anovulation happens when an egg is not released in the menstrual cycle

Complications caused due to irregular periods

While irregular periods are not harmful, having them for a long time could cause other health issues, such as:

• Anemia due to iron deficiency: If your periods are frequent and heavy, you may lose a lot of blood. Since most of the iron in your body is found in the blood, irregular periods could lead to iron deficiency.

• Osteoporosis: If you don’t ovulate regularly due to infrequent/delayed periods, your estrogen levels fall. Since estrogen helps to keep your bones healthy and strong, irregular periods could increase your risk of developing osteoporosis.

• Cardiovascular disease: Due to reduced estrogen levels, irregular periods could also increase your risk of developing cardiovascular disease.

• Endometrial hyperplasia: If left untreated for long, irregular periods could increase your chances of getting endometrial hyperplasia. In this condition, the uterus lining becomes atypically thick, which could also lead to endometrial cancer.

Treatments for irregular periods

Here are some treatments for irregular periods that your Doctor could suggest:

• Hormone therapy: Taking an estrogen- and progesterone-based birth control can help increase your hormone levels. This can help:

  • Reverse the impact of no ovulation

  • Regularize your periods

  • Make your periods easier to manage

  • Reduce the symptoms of related health conditions such as PCOS

  • Improve your quality of life

• Weight management: Both the excess and lack of body fat can affect your menstrual cycle. Achieving a moderate weight, as per your Body Mass Index (BMI), can help you ovulate and regulate your cycle. 

• Nutritional therapy: A Dietician can help you figure out what you should eat to improve your hormone health. They can also help you plan your diet according to your specific dietary requirements to better regulate your periods.

• Mental health support: If the cause of your irregular periods is depression, anxiety, stress, or an eating disorder, a Doctor may recommend psychological support, such as talk therapy, nutritional counseling, and support groups. 

• Other medications: Some medications can help you ovulate and regulate your periods. The medication given would depend on the cause of your irregular periods.

When to See a Doctor

Experiencing irregular periods occasionally is common. Irregular periods due to puberty, contraception, or perimenopause usually don’t require any treatment.

However, see a doctor if:

• You’ve experienced irregular periods for long, without any obvious cause

• You are under 45 and experiencing irregular periods

• The gap between your periods is less than 21 days or more than 35 days

• Your periods last over 7 days

• The difference between your longest and your shortest menstrual cycle is at least 20 days

• Your irregular periods could be due to a medication or a health condition

• You’re experiencing irregular periods along with other symptoms like pelvic pain

• You have irregular periods and you’re trying for a baby

Your doctor will diagnose the underlying cause of your irregular periods, if any, and suggest a course of treatment based on that cause.

How to try for a baby when you have irregular periods 

Irregular periods could make it difficult for you to conceive because you may not be ovulating regularly. In case of skipped periods, ovulation may not happen for months.

If you have irregular periods and are trying for a baby, having sex every 2-3 days can help. You could also track your ovulation period using our free Ovulation Calculator. Since the cycle length varies for irregular periods, to determine the average length of your menstrual cycle, add the number of days in three menstrual cycles and divide the total by three. 

You may need to consult a Gynecologist or a Fertility Doctor if you’re struggling to get pregnant naturally. 

Learn more about ovulation and how to get pregnant fast. If you have any more questions or concerns about irregular periods, feel free to ask our Doctors for advice.