An Overview of Anovulatory Bleeding

Causes, Treatment and Why a Period May Be Irregular

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Anovulatory bleeding describes a specific type of abnormal menstrual cycle in which the ovaries do not release an egg (ovulate). For you to have a normal menstrual cycle and what is considered a normal bleeding pattern, ovulation is necessary. When you ovulate, you trigger certain hormonal changes so that, if you don’t get pregnant, you will have a withdrawal bleed as your next cycle begins, resulting in normal interval menstrual cycles. Studies in premenopausal women suggest that in 92%–97% of cycles, an egg is released.

Anovulatory bleeding is one cause of abnormal uterine bleeding (AUB). AUB is characterized by irregular, prolonged, and usually heavy bleeding. Younger women and those in menopausal transition are most likely to experience anovulatory bleeding. It is a frequent complaint, affecting up to one-third of women of childbearing age.

This article will cover common causes of non-ovulatory bleeding and what an anovulatory period is like. It also discusses possible treatments and complications.

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What Causes Anovulatory Bleeding?

It is common for most women to experience an occasional anovulatory cycle. Physical or psychological stressors such as many sleepless nights studying for an exam, training for a marathon, extended travel, illness, or the death of a loved one can trigger stress hormones that can suppress your ovulation.

Usually, in these cases, you will miss a cycle or perhaps two. If you have associated abnormal uterine bleeding, it will likely be only minimal irregular spotting. After the acute event, your body regulates itself and you return to your normal menstrual cycles.

A common cause of anovulatory bleeding occurs at the two extremes of the menstrual cycle. During adolescence, the hormonal cascade that controls menstruation is maturing. During this time, hormonal imbalances can occur that result in heavy and irregular bleeding patterns.

During the perimenopausal transition, similar hormonal imbalances can happen that result in irregular bleeding patterns.

Obesity is a common cause of this type of abnormal uterine bleeding. Obesity alone or in combination with polycystic ovarian syndrome (PCOS) may result in frequent anovulatory cycles, resulting in heavy and irregular bleeding. PCOS affects 70% of women with anovulation.

Uncontrolled diabetes, thyroid dysfunction, hyperprolactinemia, and the use of certain medications such as steroids, antipsychotics, or antiepileptics may also result in anovulatory bleeding.

What Is an Anovulatory Period Like?

When you do not ovulate, the lining of your uterus, or endometrium, becomes disordered and unstable and begins to shed randomly. This results in an irregular bleeding pattern. This type of bleeding may be heavier and last longer than your normal menstrual bleeding (anovulatory bleeding); it may be light or just spotting; or you may not bleed at all. What all anovulatory bleeding has in common is that it occurs at irregular intervals.

Symptoms of anovulation include:

  • Missed periods (amenorrhea)
  • Light bleeding or spotting during periods
  • Excessive, prolonged bleeding during periods
  • Widely varying cycle lengths (e.g., one month your cycle is 22 days, the next it's 33)
  • Reduced or absent cervical mucus (vaginal discharge that becomes heavier just before and during ovulation)
  • Lack of premenstrual symptoms (e.g., breast tenderness, fluid retention)
  • Irregular basal body temperature

Some anovulatory cycles occur without any noticeable signs.

With some underlying conditions, if ovulation does not occur for several cycles, the lining of the uterus will continue to build up. Often a woman will miss one or more of her periods, or bleed lightly for several months, before experiencing the heavy, prolonged bleeding characteristic of abnormal uterine bleeding.

How Is Anovulatory Bleeding Treated?

Abnormal uterine bleeding caused by anovulation is typically managed with hormonal options and lifestyle changes.

  • Hormonal options: These hormonal options work to stabilize the endometrium and to counteract the hormonal imbalance that happens when you do not ovulate. Common treatment options include the oral contraceptive pill and the progestin-containing IUD.
  • Weight loss: If you are obese, weight loss is very important. Even relatively small amounts of weight loss can restore your ovulation.

As always, if you are concerned about irregular bleeding or any problems with your menstrual cycle be sure to discuss it with your healthcare provider.

Complications of Anovulatory Bleeding

There are several conditions associated with anovulatory bleeding which may lead you to seek medical treatment, including:

  • Iron deficiency anemia resulting from a chronic (long-term) state of anovulation
  • Infertility related to ovulatory dysfunction
  • Endometrial cancer
  • PCOS

You should have a medical evaluation for anovulation if you regularly miss periods, have other symptoms (such as fatigue, excess body hair, or weight fluctuations), or if anovulatory bleeding becomes routine or chronic.

Summary

Anovulatory bleeding is one cause of abnormal uterine bleeding. It occurs as an abnormal period during which an egg is not released. Abnormal uterine bleeding is described as prolonged, irregular, and most often heavy bleeding. Younger women and those in menopausal transition are most likely to experience anovulatory bleeding.

There are several possible causes including PCOS, stress, hormone disruption, and certain medications. Treatment centers around the cause of the bleeding, with hormone therapy a common option. Complications can include conditions like infertility and cancer, so it is important to consult your healthcare provider if you have other symptoms or if anovulatory bleeding becomes chronic.

8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Tracee Cornforth
Tracee Cornforth is a freelance writer who covers menstruation, menstrual disorders, and other women's health issues.