Ovarian cysts are a common health concern for many people with ovaries. Most cysts are harmless and go away on their own, but some can cause pain or other symptoms. Understanding what ovarian cysts are, what causes them and when to get help can make a big difference in your health.

What is an ovarian cyst?

An ovarian cyst is a fluid-filled sac that forms on or inside an ovary. According to Nebraska Medicine OB-GYN Candace Giles, DO, FACOG, ovarian cysts can appear during your reproductive years and even after menopause.

Many cysts are functional, meaning they form as part of a normal menstrual cycle.

• Each month, a small fluid sac forms to support a growing egg.
• During ovulation, that sac usually breaks to release the egg.
• If you become pregnant, another cyst may form to support early pregnancy.

These types of cysts are normal and usually go away on their own.

Common causes of ovarian cysts

Not all ovarian cysts are related to ovulation. Other conditions can cause cysts to form, including:

• Polycystic ovary syndrome (PCOS): “People with PCOS often have many small cysts around the ovary,” says Dr. Giles. “On an ultrasound, these cysts can look like a string of pearls. PCOS often causes symptoms like irregular periods, acne or difficulty getting pregnant.”
• Endometriosis: This condition can lead to endometriomas, which are cysts formed from endometrial tissue. These cysts can cause pelvic pain, especially during periods.
• Simple cysts: These cysts contain clear fluid and can grow quite large, sometimes causing pressure or discomfort.
• Complex cysts: These cysts can contain irregular contents or structures such as solid components, blood or multiple chambers (separations). They can also contain other types of tissue such as skin, hair or teeth. These are called dermoid cysts.
• Infected cysts or abscesses: A cyst can become infected and turn into an abscess. This can spread to nearby structures like the fallopian tubes.

Common symptoms of ovarian cysts

Symptoms can vary widely. Some people never feel any symptoms at all. Others may experience:

• Dull, sharp or aching pain in the abdomen or pelvis.
• Sudden or severe pain, especially if a cyst bursts.
• Bloating or pressure in the lower belly.
• Pain during sex.
• Bladder or bowel problems, such as pressure or trouble emptying.
• Lower back pain.

Cysts are often found by accident during imaging for another health issue or during a routine pelvic exam.

How are ovarian cysts diagnosed?

Ovarian cysts are usually diagnosed by an OB-GYN. An evaluation may include:

• Medical history: Symptoms, menstrual cycle and any past health issues.
• Pelvic exam: Checking for swelling or tenderness around the ovaries.
• Pelvic ultrasound: One of the most common tools used to determine size, shape and type of cyst.
• Blood tests: Ordered only when needed to evaluate specific cyst types.

When to seek medical care for ovarian cysts

You can start by seeing your OB-GYN or primary care provider if your symptoms are mild or slow to develop. However, some symptoms need faster attention.

Call your doctor if you have:

• Pain that lasts more than a few days.
• Bloating that does not improve.
• Pain during sex or bowel movements.
• Irregular periods.

Seek emergency care if you have:

• Sudden, severe pelvic or abdominal pain.
• Pain that does not improve with rest, hydration or over-the-counter pain medicine.
• Pain with fever, vomiting or dizziness.

These can be signs of a serious problem, such as ovarian torsion or a cyst rupture.

Ovarian torsion: A medical emergency

Large cysts can increase the risk of ovarian torsion, which happens when the ovary twists around its blood supply. Dr. Giles describes torsion pain as:

• Severe and sudden.
• Usually located in the lower abdomen or pelvis.
• Sometimes on one side, but can spread.
• Not relieved by typical pain medicine.
• Usually constant, but sometimes comes in waves.

Ovarian torsion needs urgent surgical treatment to save the ovary.

Cyst rupture

Cysts can break open (rupture). “This can cause sharp, sudden pain,” says Dr. Giles. “Some ruptures are minor, but cysts that contain blood—called hemorrhagic cysts—can be more painful and may need medical evaluation.”

Treatment options for ovarian cysts

Watchful waiting: Many cysts go away without treatment. Your doctor may suggest:

• Monitoring your symptoms.
• Repeating an ultrasound in 6 to 12 weeks. 

Medication: Hormonal pills or other forms of birth control can help prevent new cysts from forming in the future.

Surgery: Surgical removal of cysts may be needed if:

• The cyst is large.
• The cyst does not go away over time.
• The cyst causes ongoing or severe pain.
• There is concern about torsion or another complication.

Most surgery is done with minimally invasive laparoscopy, which uses small incisions and has a shorter recovery time. 

Types of surgery include:

• Cystectomy: Removing just the cyst.
• Oophorectomy (rare): Removing the ovary if necessary.

PCOS treatment 

“In PCOS, cyst removal is usually not needed,” says Dr. Giles. “Treatment focuses instead on managing symptoms such as irregular periods, excess hair growth or fertility concerns.”