How Big Is an Ovary? 6 Causes of Enlarged Ovaries

    Updated 14 January 2021 |
    Published 23 December 2019
    Fact Checked
    Reviewed by Olga Adereyko, MD, Primary Care Physician, General Practitioner, Medical Consultant
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    Having an enlarged ovary can be alarming. Depending on your age and menstrual cycle, however, it can be quite normal to have swollen ovaries from time to time. 

    The size of ovaries changes throughout the cycle. There are also several reasons you may have swollen ovaries. If you’re wondering if you have enlarged ovaries or about the possible causes of your swollen ovaries, then read on. We’ve listed common causes of an enlarged ovary, as well as ways to diagnose and treat it if needed. 

    Average ovary size

    An ovary is an oval-shaped gland that rests on either side of the uterus. These glands produce both eggs and hormones. So how big is an ovary?

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    In an adult, the average ovary size is 3–5 centimeters long. Once the number of eggs depletes and the body begins to enter menopause, the size of ovaries will decrease to about 2–3 centimeters or less. 

    But how can you tell if you don’t have normal ovary size? And what can you do if they’re enlarged?

    Diagnosis of enlarged ovaries

    There are several signs you can pay attention to that may indicate you have enlarged ovaries. If you notice any of the listed symptoms, talk to your doctor about your ovaries. 

    Enlarged ovaries can be caused by different underlying conditions. The symptoms of these conditions might include:

    Rarely, an ovary can become so enlarged that it can be felt in the pelvic area. 

    Sometimes an enlarged ovary is completely normal, and so are the symptoms associated with them. If you experience these symptoms frequently or don’t get any relief, talk to your doctor because it might indicate that medical attention is needed for an underlying cause.

    There are a few ways your doctor can test you for an enlarged ovary. Depending on your symptoms and age, they may suggest one or more of the following:

    • Ultrasound
    • CT scan
    • MRI
    • Doppler flow study
    • CA-125 blood test
    • Pregnancy test
    • Hormone test

    If you do have enlarged ovaries, there are a few causes for them. Some are completely normal, but others may be cause for concern. 

    Causes of enlarged ovaries

    So why would you be experiencing an enlarged ovary? How can you tell if your enlarged ovaries are simply a product of normal hormone function? 

    These are a few causes of enlarged ovaries:

    • Ovulation: As an egg matures and prepares to be released, it can cause the ovary it’s in to swell. When the ovary releases the egg, ovulation occurs. This usually happens around day 14 of a 28-day cycle. Ovulation can cause a change or increase in vaginal discharge and slight cramping. Ovulation is a completely normal and healthy body function. 
    • Ovarian torsion: Ovarian torsion happens when the ovary and part of the fallopian tube get twisted. This is a medical concern, because the torsion may cut the blood supply to the ovary. Without an adequate blood supply, the tissue can die, and the ovary itself can become infected. Symptoms of ovarian torsion include nausea, vomiting, and pain in the lower belly or pelvis. 
    • Follicular cyst: This ovarian cyst forms when a dominant follicle doesn’t release the egg that has matured inside it. Instead, it grows and becomes a cyst. This form of ovarian cyst usually doesn’t cause any symptoms and goes away on its own.
    • Corpus luteum cyst: After the follicle releases the egg, the follicle begins producing estrogen and progesterone for conception, turning into a structure called the corpus luteum. Sometimes, fluid accumulates inside the follicle, causing the corpus luteum to grow into a cyst. 
    • Endometrioma: This type of cyst forms from endometrium tissue, the same tissues that line the uterus. This is a common symptom for women who have endometriosis. Endometriosis is a condition in which endometrial tissue implants in various places along the pelvis. The tissue normally swells each month and sheds blood to create our menstrual cycle, but in an endometrioma cyst (ovarian in this case), it swells but has nowhere to go. This cyst can be quite painful, causing pain during sex, painful periods, and heavy bleeding. If left untreated, it can cause permanent damage to the ovaries and even become cancerous. 
    • Dermoid cyst: A dermoid cyst forms from embryonic cells as an embryo develops. They contain tissues that are normally found elsewhere on the body, such as hair, skin or teeth, oil glands, and hair follicles. These tissues release their own substances, such as sebum, which make your ovaries swell. These are usually quite harmless. They don’t tend to cause symptoms
    • Polycystic ovarian syndrome (PCOS): Most women with polycystic ovary syndrome produce excess male sex hormones (androgens). Abnormal levels of androgens and other sex hormones prevent normal release of egg cells from the ovaries and thus form cysts. There are a plethora of symptoms that signal PCOS, but there is no current treatment that will cure it. Your doctor may prescribe certain medications that can ease the symptoms, which can include excess facial or body hair, fewer periods than normal, and difficulty getting pregnant. 
    • Non-cancerous (benign) tumor: Sometimes a tumor can grow in the ovaries.  This is a growth that does not spread (metastasize) to other parts of the body. Non-cancerous tumors are not usually life-threatening 

    Functional ovarian cysts tend to clear up on their own in a matter of months. They don’t normally cause many symptoms, and doctors don’t need to treat them. If they are larger than normal or cause severe symptoms such as pain or bloating, your doctor may need to perform surgery to remove the cysts. 

    Benign tumors and cysts usually do not cause symptoms. Symptoms that sometimes occur are:

    • Unusual bleeding from the vagina
    • Pain in the abdomen as the tumor or cyst increases in size

    Small tumors may go away without treatment. Larger ones may need surgery to be removed. 

    Rarely, cancerous tumors develop in the ovaries. They don’t tend to cause any symptoms unless the cancer has spread. Let your doctor know right away if you experience any of these symptoms:

    • Swollen belly
    • Swollen legs
    • Pain in the pelvis or lower belly
    • Abnormal discharge from the vagina
    • Abnormal bleeding from the vagina
    • Frequent or urgent need to pee
    • Pain during sex
    • Sudden weight change
    • Changes in your period

    A doctor can use testing to determine if you have a larger-than-normal ovary size. If necessary, the doctor may suggest treatment for the cause of the swelling. 

    Treatment options for enlarged ovaries

    There are normal causes of swollen ovaries, and there are some abnormal causes. Some do not require treatment, as they tend to clear up within 8 to 12 weeks. Others are more serious.

    If left untreated, they can cause complications like infection and difficulty conceiving, in addition to the underlying condition remaining undiagnosed. If an enlarged ovary is due to a serious health concern, a doctor may prescribe some of the following treatments. It depends on the underlying condition. For example:

    • Birth control: Certain birth control medications help prevent frequent cysts.
    • Surgery: Surgery can help fix a torsion, persistent cysts, and ovarian cancer. 
    • Chemotherapy: If you have ovarian cancer, chemotherapy can help eliminate cancer cells.

    Factors that indicate surgery may be necessary include:

    • Cysts that do not go away after three months
    • Cysts larger than 5–10 centimeters 
    • Cysts that are increasing in size
    • Tumors that are increasing in size
    • Ovarian cancer

    When to see a doctor

    Because cysts are a common cause of an enlarged ovary, you may not have to do anything. Many cysts clear up on their own within three months, prompting a return to normal ovary size, but consult with your health provider first.

    If your symptoms are abnormal or painful and start up suddenly, then you should talk to your doctor. They may want to run some tests and see if you have a more serious condition. Keep track of the following symptoms:

    • Abdominal pain 
    • Feeling of fullness
    • Heavy bleeding
    • Painful sex
    • Abnormal vaginal discharge
    • Missed periods

    Keep a journal of your symptoms and track your period so you can map out your cycle. This can help you understand when your symptoms are worse and when they occur during your cycle. This is valuable information for your doctor.


    An enlarged ovary can happen as a natural part of the menstrual cycle. If you have a larger-than-normal ovary size that doesn’t correspond to ovulation or you are past menopause, then it may be cause for concern.

    Tracking your symptoms and cycle helps you stay in the know when things change. Letting your doctor know about your symptoms can lead to early detection if something is wrong.

    History of updates

    Current version (14 January 2021)

    Reviewed by Olga Adereyko, MD, Primary Care Physician, General Practitioner, Medical Consultant

    Published (23 December 2019)

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