What Is The Main Cause of Ovarian Cysts?

Medically Reviewed on 3/3/2022

What are ovarian cysts?

The main causes of ovarian cysts may include hormonal imbalance, pregnancy, endometriosis, and pelvic infections.
The main causes of ovarian cysts may include hormonal imbalance, pregnancy, endometriosis, and pelvic infections.

Ovarian cysts are sacs of fluid that form on either the ovary or its surface. Women possess two ovaries which sit on either side of the uterus. The ovaries release eggs every month as a part of a woman’s menstrual cycle.

About 7% of women have an ovarian cyst at some point in their life. For most women, ovarian cysts are harmless and painless. In fact, ovarian cysts often resolve on their own without treatment.

However, in some cases, an ovarian cyst can cause pain or develop into more serious complications. Ovarian cysts may be cause for concern when they are accompanied by sudden pain or other symptoms.

Rarely, an ovarian cyst may develop into a more serious condition. If the cyst grows too large, the ovary can twist. This results in a dangerous condition known as ovarian torsion. Some cysts also run the risk of rupturing, which can cause internal bleeding. Both conditions can arise without warning and require medical intervention.

It is important to understand the causes and symptoms of cysts. Keeping up with your regular pelvic exams can help you stay healthy. Ovarian cysts are primarily caused by hormonal imbalance, endometriosis, or the natural occurrence of a corpus luteum cyst.

Signs and symptoms of ovarian cysts

Though some ovarian cysts occur without pain and cause no harm, some women with cysts experience significant symptoms. The signs and symptoms of ovarian cysts can include:

Pelvic pain

When an ovarian cyst develops, some women experience moderate to severe pain. The pain may occur as a dull, constant ache to a sharp or sudden pain.

For many women, pelvic pain is a common symptom of ovarian cysts. This pain often occurs during or after sex.

Beyond pelvic pain during intercourse, some women experience aches or low back pain, cramping in the legs, or breast tenderness.


Bloating, which often occurs with a feeling of abdominal heaviness or fullness, is a common symptom of an ovarian cyst. Bloating can fluctuate in intensity throughout your cycle.

Weight gain

Ovarian cysts can sometimes be accompanied by drastic or unusual weight gain. This can occur when the ovarian cyst is the result of a hormonal imbalance.

Painful and heavy menstruation

A common symptom of ovarian cysts are painful menstrual periods. Many women also experience heavy bleeding, very painful cramping, and severe bloating.

Bathroom complications

Some cysts occur with symptoms of trouble urinating, trouble defecating, difficult bowel movements, and urinary urgency.

Abnormal bleeding

If you are experiencing bleeding outside of your menstrual period, spotting, or unusually heavy bleeding during your menstrual period, you may have developed an ovarian cyst.


Where does ovarian cancer occur? See Answer

Types of ovarian cysts

Depending on the cause of an ovarian cyst, there are several different types of ovarian cysts:

Follicular cyst

Follicular cysts are functional cysts that form if the ovarian follicle does not rupture or release the egg. Instead, it continues to grow as a cyst.

Corpus luteum cyst

A corpus luteum cyst is another form of functional cyst, which occurs when the follicle bursts but continues to grow as a cyst. Most corpus luteum cysts are harmless, painless, and resolve on their own.

Dermoid cysts

Dermoid cysts form from embryonic cells and often contain hair, skin, or teeth tissues.


These cysts are filled with a fluid or mucus-like material and occur on the surface of the ovary.


Endometriomas are the result of endometriosis, in which uterine cells grow outside of the uterus.

Causes of ovarian cysts

There are several potential causes of ovarian cysts. Underlying causes may include:

Hormonal imbalance

Hormonal imbalance can lead to a higher chance of developing an ovarian cyst. Hormonal imbalance can be triggered by ongoing fertility treatments or other underlying issues.


Once the egg is released from the follicle, corpus luteum cysts can sometimes continue growing into a woman’s pregnancy. Many times, the cyst may resolve on its own during pregnancy or after.


Endometriosis is a fairly common condition that causes the endometrial cells from the uterus to grow beyond the uterine walls. Endometrial tissues can attach to your ovaries and form a cyst.

Pelvic infections

Pelvic infections can lead to the formation of cysts if the infection reaches the ovaries.

Previous cysts

If you have previously experienced an ovarian cyst, you are likely to develop another.

When to see the doctor for ovarian cysts

If you experience any painful symptoms associated with an ovarian cyst, you should seek medical treatment. You should seek immediate treatment if you experience any of the following symptoms:

These symptoms may indicate a ruptured cyst or ovarian torsion, which can be dangerous if left untreated.

Diagnosing ovarian cysts

Ovarian cysts can often be diagnosed during a routine pelvic exam. Depending on the type of the cyst, your doctor will recommend additional tests in order to determine a treatment plan. Potential tests may be:

  • Pregnancy test
  • Pelvic ultrasound
  • Laparoscopic surgery

Treatments for ovarian cysts

Once you have been diagnosed with an ovarian cyst, your doctor may recommend:

  • Follow-up appointments to monitor the growth of the cyst
  • Hormonal birth control to slow the growth of your cyst
  • Surgery to remove the cyst

How would I know if I have ovarian cancer?

When cancer begins in the ovaries it is called ovarian cancer. The ovaries are a pair of organs that are a part of the female reproductive system. Each ovary is an oval-shaped organ, roughly two inches long. They are located in the pelvis on either side of the uterus. Their main functions include producing eggs or ova and the female sex hormones (estrogen and progesterone).

If a woman has ovarian cancer, they may or may not experience any significant symptoms. Ovarian cancer is rarely diagnosed in its early stages due to the lack of any typical signs and symptoms. When present, the symptoms may include

Who gets ovarian cancer?

Any female can get ovarian cancer. Recent studies suggest that ovarian cancer may begin in the part of the fallopian tubes near the ovaries (distal end). The definitive cause of ovarian cancer is not known. Certain conditions may increase the risk of getting ovarian cancer. Having any of the risk factors does not necessarily mean a woman will get ovarian cancer. Some women may not get ovarian cancer despite the risk factors whereas some may get the condition despite the absence of any risk factors. Some of the important risk factors for ovarian cancer include

  • Being middle-aged or older.
  • Having a family history of ovarian cancer, breast cancer or colorectal cancer (this means any of the first-degree relatives, such as mother, sister, or daughter have had any of these cancers).
  • Inheriting certain abnormal genes, namely BRCA and BRCA2, or the gene associated with Lynch syndrome or Peutz-Jeghers syndrome.
  • Having a positive personal history of cancer of the breast, uterus, colon or rectum.
  • Being obese or overweight.
  • Having a certain ethnic background (Eastern European or Ashkenazi Jewish).
  • Having endometriosis (a condition in which the tissue lining the uterus grows elsewhere in the body).
  • Using fertility treatment (such as in vitro fertilization or IVF) may increase the chances of noncancerous or cancerous tumors of the ovaries.
  • Never having been pregnant or carrying a pregnancy to term.
  • Smoking (it typically increases the risk for mucinous ovarian cancer).
  • Applying talcum powder to the genital area or using talc on sanitary napkins, condoms or diaphragms.
  • Taking the hormone, estrogen, without progesterone for 10 years or more.

If a woman has any of the risk factors, particularly a family history of ovarian, breast or colorectal cancer, she must consult the doctor for screening tests.

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How do doctors diagnose ovarian cancer?

Doctors may diagnose ovarian cancer by

  • Taking a detailed medical history including the details about the symptoms, any underlying health conditions and any significant personal or family history of ovarian, breast or colorectal cancer. 
  • Performing a thorough physical examination, particularly a pelvic exam to look for a bulky ovary or signs of fluid in the abdomen (called ascites).
  • Ordering imaging tests such as ultrasound, computed tomography (CT) scan, magnetic resonance imaging (MRI) scan, positron emission tomography (PET) scan and barium enema X-ray, to see whether the cancer has spread to the large bowel. A chest X-ray may also be done to check whether the cancer has spread to the lungs.
  • Getting a biopsy done that includes taking a small tissue sample from the tumor and examining it under a microscope. The biopsy sample may also help stage and grade the cancer and determine the presence of special proteins (such as hormone receptors) that help plan a proper treatment regimen.
  • Performing a laparoscopy to examine the pelvic organs, including the ovaries, by using a thin, flexible tube with a light source and camera (laparoscope) inserted into the abdomen via a small cut (incision).
  • Ordering certain blood tests, such as blood counts and clotting time tests, to check the levels of certain important substances, such as human chorionic gonadotropin (HCG), lactate dehydrogenase (LDH), alpha-fetoprotein (AFP) and cancer antigen 125 (CA-125), which are linked with ovarian cancer.
Medically Reviewed on 3/3/2022
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