An Overview of Anovulatory Bleeding

Causes, Treatment and Why a Period May Be Irregular

Anovulatory bleeding describes a specific type of abnormal uterine bleeding. In order for you to have a normal menstrual cycle and what is considered a normal bleeding pattern, you have to ovulate. 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.

Doctor and Patient, Abdomen Palpation
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What Happens When You Don't Ovulate

When you do not ovulate, this hormonal cascade is not initiated. Not only are you not able to conceive during an anovulatory cycle, but you also will not have your regular period. Anovulation does not always result in abnormal bleeding, at least not immediately.

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 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.

Anovulatory bleeding that might bring you to seek medical attention usually results from a more chronic state of anovulation. With some underlying conditions, if ovulation does not occur for several cycles, the lining of the uterus still builds up. However, because you did not ovulate, your body did not get the trigger to shed the lining of your uterus, aka having your period. 

When this happens, the lining of your uterus, or endometrium, becomes disordered and unstable and it begins to randomly shed. This results in bleeding that is not in a regular pattern. This type of bleeding can be heavier and last longer than your normal menstrual bleeding. Again, depending on the underlying cause of the anovulation, the bleeding may simply be light spotting. What all anovulatory bleeding has in common is that it occurs at irregular intervals.

Common Causes

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 to 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.


Abnormal uterine bleeding caused by anovulation is typically managed with 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. If you are obese weight loss is very important. Even relatively small amounts of weight loss and 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.

4 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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  2. Wilcox AJ, Weinberg CR, Baird DD. Timing of sexual intercourse in relation to ovulation. Effects on the probability of conception, survival of the pregnancy, and sex of the baby. N Engl J Med. 1995;333(23):1517-21. DOI: 10.1056/NEJM199512073332301

  3. Rebar R. Evaluation of Amenorrhea, Anovulation, and Abnormal Bleeding. In: Feingold KR, Anawalt B, Boyce A, et al., editors. Endotext [Internet]. South Dartmouth (MA):, Inc.; 2000-. PMID: 25905367

  4. Farrukh JB, Towriss K, McKee N. Abnormal uterine bleeding: Taking the stress out of controlling the flow. Can Fam Physician. 2015;61(8):693–697. PMID: 26273083

By Tracee Cornforth
Tracee Cornforth is a freelance writer who covers menstruation, menstrual disorders, and other women's health issues.