Ovarian Cysts on Ultrasound: What They Mean and What Happens Next

Seeing the words “ovarian cyst” on an ultrasound report can be unsettling—especially when the report also uses terms like simple, complex, solid, or septations.

The reassuring truth is that ovarian cysts are very common. According to the American College of Obstetricians and Gynecologists (ACOG), most are benign, and many go away without treatment. Still, the right next step depends on more than the word cyst. Your age, symptoms, menstrual status, and the cyst’s size and appearance all matter.

In my latest video, I explain how OB/GYNs evaluate ovarian cysts on ultrasound and what may happen next.

Watch the full video: Ovarian Cysts on Ultrasound: What They Mean and What Happens Next | OBGYN Explains

What is an ovarian cyst?

An ovarian cyst is a sac or pocket filled with fluid or other tissue that develops in or on an ovary. Cysts can occur during the reproductive years or after menopause.

Many ovarian cysts are found incidentally. In other words, you may have no symptoms at all, and the cyst appears on imaging performed for another reason.

Some cysts can cause symptoms such as:

• A dull or sharp ache in the lower abdomen or pelvis
• Pain during certain activities
• A feeling of pelvic pressure or fullness
• Sudden, severe pain if a cyst bleeds, ruptures, or causes the ovary to twist

Symptoms alone cannot tell us what kind of cyst is present, which is one reason ultrasound is so useful.

What types of ovarian cysts are common?

Not every ovarian cyst forms for the same reason. ACOG describes several types, including:

Functional cysts

Functional cysts are the most common type. They develop as part of the normal menstrual cycle and often cause no symptoms. Many resolve on their own, commonly within about six to eight weeks.

Teratomas, also called dermoid cysts

A teratoma is usually a benign growth that may contain different types of tissue. These cysts can be present from birth and may enlarge during the reproductive years. Malignant transformation is rare.

Cystadenomas

A cystadenoma is usually a benign tumor that develops on the outer surface of an ovary. Some can become quite large even though they are not cancerous.

Endometriomas

An endometrioma is an ovarian cyst associated with endometriosis. These cysts form when endometriosis involves an ovary.

The type of cyst cannot always be determined with certainty from a single image. Your clinician interprets the ultrasound pattern together with your health history and symptoms.

What does an ultrasound tell us about an ovarian cyst?

Ultrasound uses sound waves to create images of the pelvic organs. The exam may be performed over the abdomen, through the vagina, or with both approaches.

When evaluating an ovarian cyst, clinicians look at features such as:

• Size: How large is the cyst?
• Location: Is it clearly arising from an ovary?
• Contents: Is it filled with fluid, solid tissue, or a mixture?
• Shape and borders: Does it have a smooth, regular appearance?
• Internal structure: Are there walls, divisions, nodules, or other features inside it?
• Blood flow: Does Doppler imaging show blood flow in or around certain areas?

A simple cyst generally appears as a thin-walled, fluid-filled space. That pattern is often reassuring, particularly in someone who has not gone through menopause. A complex cyst contains additional internal features, but the word complex is a description—not a diagnosis of cancer.

The complete report matters. One isolated word should not be interpreted without the rest of the ultrasound findings and your clinical context.

Does an ovarian cyst mean cancer?

Usually, no. Most ovarian cysts are benign.

However, some ovarian masses require closer evaluation. Concern may be influenced by the appearance and size of the mass, whether it changes over time, your symptoms, your age and menopausal status, and your personal or family history of breast or ovarian cancer.

An ultrasound cannot always provide a final diagnosis. When a finding is not clearly benign, your clinician may recommend additional imaging, bloodwork, consultation with a specialist, or surgery.

What usually happens after an ovarian cyst is found?

The next step is individualized. Common possibilities include the following.

Watchful waiting

Watchful waiting means monitoring the cyst rather than treating it immediately. Your OB/GYN may recommend a repeat ultrasound to see whether the cyst disappears, becomes smaller, stays stable, or changes in appearance.

ACOG notes that many cysts resolve after one or two menstrual cycles. The timing of a follow-up ultrasound depends on the specific finding and your circumstances.

Blood tests

In some situations, a clinician may order a blood test such as CA 125. This result is not a stand-alone cancer test. CA 125 can be elevated for reasons other than cancer, and its meaning depends on the ultrasound findings, physical exam, age, and menopausal status.

Other blood tests may be recommended when a particular type of ovarian mass is suspected.

Additional imaging

Sometimes another ultrasound or a different type of imaging is recommended to better characterize a mass or determine whether it is changing.

Surgery

Surgery may be recommended when a cyst is very large, causes significant symptoms, persists or grows, has concerning features, or raises suspicion for cancer.

A cystectomy removes the cyst while preserving the ovary when possible. In some circumstances, the ovary itself may need to be removed; this is called an oophorectomy.

The surgical approach depends on factors such as the cyst’s size and appearance, your age, whether you hope to preserve fertility, your symptoms, and your cancer risk. When a cyst appears benign, minimally invasive surgery is often used.

Why do age and menopause matter?

Ovarian cysts are common during the reproductive years because the ovaries regularly develop follicles as part of ovulation. Functional cysts are therefore common before menopause.

After menopause, the ovaries are no longer ovulating, so a new ovarian mass is considered in a different clinical context. This does not mean that every postmenopausal cyst is cancerous. It does mean that your clinician may use different follow-up thresholds or recommend additional evaluation.

When is an ovarian cyst an emergency?

One complication of an ovarian cyst is ovarian torsion, which happens when the ovary twists. This can interfere with blood flow to the ovary and requires urgent evaluation.

Seek urgent medical care for sudden, severe pelvic or abdominal pain, especially when it occurs with nausea or vomiting. A bleeding or ruptured cyst can also cause sudden severe pain and should be evaluated promptly.

Do not wait for a routine appointment if you are experiencing severe or rapidly worsening symptoms.

Questions to ask your OB/GYN

If an ultrasound shows an ovarian cyst, helpful questions may include:

• Does this look like a simple cyst or a more complex mass?
• What features are reassuring?
• Does anything on the ultrasound need closer evaluation?
• Do I need another ultrasound? If so, when?
• Would bloodwork or additional imaging be useful?
• What symptoms should prompt me to call the office?
• What symptoms would require urgent or emergency care?
• If surgery is recommended, would the goal be to remove the cyst, the ovary, or both?
• How could treatment affect fertility or hormone function?

It is completely reasonable to ask your clinician to translate the wording in the radiology report into plain language.

The bottom line

An ovarian cyst on ultrasound is a finding—not a final diagnosis.

Most ovarian cysts are benign, and many go away without treatment. The most useful questions are what the cyst looks like, whether you have symptoms, whether you have gone through menopause, and whether the finding changes over time.

Your OB/GYN may recommend observation, repeat imaging, bloodwork, additional imaging, or surgery depending on the full picture. Understanding why a particular plan was recommended can make an uncertain finding feel much more manageable.

For a visual explanation of reassuring and concerning ultrasound features, follow-up options, surgery, and ovarian torsion, watch my full video: Ovarian Cysts on Ultrasound: What They Mean and What Happens Next

Sources & Further Reading

• ACOG: Ovarian Cysts
• ACOG: Ultrasound Exams
• ACOG: Evaluation and Management of Adnexal Masses

Medical Disclaimer: This content is provided for general educational and informational purposes only and is not intended to be, and should not be considered, medical advice, diagnosis, or treatment. It does not create a physician-patient relationship. Medical decisions should be made with a qualified healthcare professional who knows your personal medical history. Always consult your own doctor or other qualified healthcare provider with questions about your health, symptoms, medications, or treatment options. If you believe you may be experiencing a medical emergency, seek emergency medical care immediately.