What is irregular menstruation like and what are its causes?

By (embryologist), (embryologist) and (embryologist).
Last Update: 05/06/2022

A woman has an irregular menstrual cycle when the time interval between one menstrual period and another is outside 21-35 days.

In other words, a menstruation is irregular when less than 21 days or more than 35 days pass between one vaginal bleeding and another.

As for the duration of bleeding, it usually lasts from 3 to 8 days. In the case of irregular women, menstrual bleeding may last longer or shorter. In addition, the amount of bleeding is usually abundant and the woman feels intense pain.

Why does this happen?

Irregular menstrual cycles are those in which the length of the menstrual cycle is outside the normal range. It is important to clarify that irregular menstruation is only a symptom and should never be considered a disease.

The reasons why a woman may have an irregular menstrual cycle can be classified as:

are due to delayed puberty, absence of ovaries, or hormonal disorders.
as a consequence of genital infection, ovarian cancer, early menopause or pituitary alternation.

In addition, recurrent miscarriages, breastfeeding or after childbirth can also cause a woman to have menstrual cycles of irregular length.

How is irregular menstruation detected?

Some symptoms that will alert you to make an immediate consultation about a possible irregular period are the following:

  • Absence of Menstruation.
  • Early menstruation.
  • Menstruation too heavy or too light.
  • Painful menstruation.
  • Hemorrhages that occur outside of menstruation.

These symptoms are not usually transient, but recur for at least three months.

Treatments for irregular menstruation

There are several treatments for irregular periods. First, a gynecological examination and blood tests will always be performed.

Depending on the characteristics of the patient, the physician will request a Pap smear or also remove a sample of the cervical mucosa to perform a colposcopy. This test allows viewing of the vagina and cervix by means of a special optical device.

Treatment will always depend on the cause of the menstrual disorder. For example, in the case of defective ovulation, a hormonal procedure will be performed.

Generally, this type of rule is not dangerous, although it should be treated to rule out the possibility of a tumor or other serious disease. Early consultation with a gynecologist always offers greater possibilities of treatment and cure.

Tips to prevent irregular periods

Although most of the time irregular menstruations are the result of the body's own nature, there are some recommendations to prevent them from occurring. Each of them is listed below:

  • Follow a healthy and varied diet.
  • Avoid sugar, refined flours, sausages and dairy products.
  • Increase physical activity gradually.
  • Control stressful situations and nerves.
  • Sufficient rest.

As home remedies, some infusions and teas also help to regulate the period in a natural way. For example, rosemary, chamomile or ginger may help regulate a woman's menstrual cycle. In addition, verbena regulates the pituitary gland and thus the production of hormones. Therefore, verbena would be indicated for women with irregular periods due to thyroid problems.

Menstruation using contraceptives

Hormonal contraceptives, such as the pill or the ring , regulate the ovarian cycle. In addition, these hormonal contraceptives are indicated for women who have pain or heavy bleeding, as they cause more stable and regular cycles. If the administration of contraceptives is discontinued after a period of time, the ovulatory pattern that the woman had before taking the contraceptives will most frequently return.

Many women are recommended hormonal contraceptives to avoid menstrual pain or dysmenorrhea. During the administration of contraceptives, the pain usually disappears and after cancellation the pain usually returns, but it may be attenuated.

FAQs from users

What do irregular periods mean after the age of 40?

By Marta Barranquero Gómez B.Sc., M.Sc. (embryologist).

Women who have menstrual disturbances after the age of 40 may be approaching the end of the reproductive stage, i.e., menopause.

What are the causes of an irregular menstruation?

By Marta Barranquero Gómez B.Sc., M.Sc. (embryologist).

Irregularities in menstruation may be due to several factors. One of them is stress or emotional stages of great intensity. This would cause an alteration at the hormonal level, causing changes in the menstrual cycle.

Other possible causes of irregular menstruation are diet, intense physical activity, drugs and thyroid gland problems. In addition, polycystic ovarian syndrome (PCOS) or the presence of uterine cysts and polyps could also be the cause of abnormal menstruation.

How do I know when my period will come if it is irregular?

By Marta Barranquero Gómez B.Sc., M.Sc. (embryologist).

It is complicated, since each month comes on a different date. That is why you should pay attention to certain signs that are related to the descent of menstruation. This is the case of intense backaches and headaches, the appearance of acne outbreaks on the face, mood swings, swelling, etc.

Does the menstrual cycle have to be regulated before AI?

By Paula Cano Calvo B.Sc., M.Sc. (embryologist).

Paula Cano, embryologist at Pronatal Fertility Clinics, answers us:

Yes. Artificial insemination or AI is a low-complexity assisted reproduction technique that consists of introducing previously capacitated semen into the patient's uterus. It is a very simple procedure that does not require anesthesia and is usually performed in a regular gynecological office. But even so, it does require hormonal treatment to control follicular growth and ovulation in order to promote pregnancy. Through this hormonal treatment or medication, the gynecologist is looking for the growth of one or two follicles and this growth is controlled by vaginal ultrasound every 2-3 days to adjust the dose of medication and prevent the growth of more follicles that can lead to a multiple pregnancy.

Why do teenage girls have irregular periods?

By Marta Barranquero Gómez B.Sc., M.Sc. (embryologist).

When menarche occurs, that is, the first menstruation in girls, it is common to suffer menstrual disturbances. Many adolescents have spotting between periods or even periods of absence of menstruation. These irregularities in the menstrual cycle disappear as the hormonal axis stabilizes.

How does pregnancy affect menstruation?

By Cristina Mestre Ferrer B.Sc., M.Sc. (embryologist).

When pregnancy occurs, the body detects it in a way that prevents menstruation in the following months.

One of the most frequent concerns of pregnant women is to know when they will get their period again after childbirth. The waiting time for menstruation when giving birth varies greatly depending on whether the woman breastfeeds the baby or not.

Breastfeeding is an anovulatory period. At the beginning there is no ovulation because the milk feedings are every two hours. As the feedings are spaced out, the body starts producing the necessary hormones again and ovulation begins. Sometimes ovulation occurs, but menstruation as such does not occur until later. Therefore, if you breastfeed, it will be necessary to use contraceptive methods to avoid becoming pregnant again while breastfeeding. Menstruation usually returns 4 to 6 months after the birth of the baby.

If the woman does not choose to breastfeed the baby, menstruation comes earlier. This usually occurs about two months after delivery.

Suggested for you

One of the main consequences of irregular menstrual cycles is menstrual delay. If you want to know more about this topic, we recommend you to visit the following article: What can be the reason for a menstrual delay?

In addition, if you are looking for a pregnancy, you may have to resort to assisted reproductive techniques. To continue reading more information about fertility treatments, you can access this link: Assisted reproduction techniques: differences and complexity.

We make a great effort to provide you with the highest quality information.

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A Imai, S Ichigo, K Matsunami, H Takagi. Premenstrual syndrome: management and pathophysiology. Clin Exp Obstet Gynecol. 2015;42(2):123-8.

D A Koutras. Disturbances of menstruation in thyroid disease. Ann N Y Acad Sci. 1997 Jun 17;816:280-4. doi: 10.1111/j.1749-6632.1997.tb52152.x . (See)

Jinju Bae, Susan Park, Jin-Won Kwon. Factors associated with menstrual cycle irregularity and menopause. BMC Womens Health. 2018 Feb 6;18(1):36. doi: 10.1186/s12905-018-0528-x (See)

Xinyu Zhou, Xin Yang. Association between obesity and oligomenorrhea or irregular menstruation in Chinese women of childbearing age: a cross-sectional study. Gynecol Endocrinol. 2020 Dec;36(12):1101-1105. doi: 10.1080/09513590.2020.1803823. Epub 2020 Aug 12.

Yeunhee Kwak, Yoonjung Kim. Irregular menstruation according to occupational status. Women Health. Nov-Dec 2018;58(10):1135-1150. doi: 10.1080/03630242.2017.1342740. Epub 2017 Aug 29.

FAQs from users: 'What do irregular periods mean after the age of 40?', 'What are the causes of an irregular menstruation?', 'How do I know when my period will come if it is irregular?', 'Does the menstrual cycle have to be regulated before AI?', 'Why do teenage girls have irregular periods?' and 'How does pregnancy affect menstruation?'.

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Authors and contributors

 Cristina Mestre Ferrer
Cristina Mestre Ferrer
B.Sc., M.Sc.
Bachelor's Degree in Biological Sciences, Genetics & Human Reproduction from the University of Valencia (UV). Master's Degree in Biotechnology of Human Assisted Reproduction from the UV and the Valencian Infertility Institute (IVI). Embryologist at IVI Barcelona. More information about Cristina Mestre Ferrer
 Marta Barranquero Gómez
Marta Barranquero Gómez
B.Sc., M.Sc.
Graduated in Biochemistry and Biomedical Sciences by the University of Valencia (UV) and specialized in Assisted Reproduction by the University of Alcalá de Henares (UAH) in collaboration with Ginefiv and in Clinical Genetics by the University of Alcalá de Henares (UAH). More information about Marta Barranquero Gómez
License: 3316-CV
 Paula Cano Calvo
Paula Cano Calvo
B.Sc., M.Sc.
Paula Cano is currently an embryologist at Pronatal Fertility Clinics, a fertility center located in Madrid. Paula studied Biology at the University of Girona and did a Master's degree in Clinical Genetics and Assisted Human Reproduction at the University of Alcalá de Henares, Madrid. More information about Paula Cano Calvo
Member number: 20364-M

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