Ovarian Cysts
Understanding common fluid-filled sacs on the ovaries, when they're concerning, and when they're part of normal ovulation
Seek Emergency Care If You Experience:
- β’Sudden, severe pelvic or abdominal pain (especially one-sided)
- β’Pain with nausea, vomiting, or fever
- β’Lightheadedness, fainting, or rapid heart rate (signs of internal bleeding)
- β’Severe abdominal distention with difficulty breathing
Call 911 or go to the nearest emergency room immediately. Do not delay care.
What They Are
Ovarian cysts are fluid-filled sacs that develop on or in the ovaries. They are extremely common in women of reproductive age. Most ovarian cysts are functional cysts related to the normal ovulatory process and are benign (not cancerous).
Every month during a normal menstrual cycle, follicles (small cysts) grow on the ovaries. Usually one follicle releases an egg (ovulation) and the others shrink away. Sometimes these follicles continue growing or fill with fluid, creating functional cysts. These typically resolve on their own within 1-3 menstrual cycles.
Why It Matters
While most ovarian cysts are benign and resolve spontaneously, they can cause:
- Pelvic pain or discomfort, especially if cysts are large or rupture
- Ovarian torsion (twisting of the ovary), a surgical emergency that can threaten ovarian blood supply
- Internal bleeding if a hemorrhagic cyst ruptures
- Anxiety about potential cancer (though cancer is rare in premenopausal women with simple cysts)
Understanding which cysts need monitoring and which require intervention helps reduce unnecessary anxiety and procedures.
Types of Ovarian Cysts
Functional Cysts (Benign)βββ
Related to normal ovulatory process. Most common type.
Other Benign Cysts
- Dermoid cysts (teratomas): Contain tissue like hair, skin, or teeth. Usually benign but don't resolve spontaneously.
- Cystadenomas: Filled with watery or mucous fluid. Can grow large.
- Endometriomas ("chocolate cysts"): Result from endometriosis. Contain old blood.
- Polycystic ovaries: Multiple small follicles seen in PCOS. Not true cysts requiring treatment.
Malignant (Cancerous) Cysts
Rare in premenopausal women. Risk increases with age, especially after menopause. Complex appearance on ultrasound (solid components, thick walls, septations) raises suspicion.
Common Symptoms
Important: Most functional cysts are asymptomatic.
Many cysts are discovered incidentally during pelvic exams or ultrasounds for other reasons. Having no symptoms is normal for functional cysts.
When symptomatic, cysts may cause:
- Dull or sharp pelvic pain (usually one-sided)
- Bloating or pelvic fullness
- Pain that worsens with intercourse, exercise, or bowel movements
Complications Requiring Emergency Care
Ovarian Torsion (Surgical Emergency)βββ
A cyst can cause the ovary to twist on its blood supply (vascular pedicle), cutting off blood flow. Requires immediate surgery to save the ovary.
Symptoms: Sudden severe one-sided pelvic pain, nausea, vomiting
Cyst Rupture
Cysts can rupture, releasing fluid into the pelvic cavity. Symptoms: Sudden sharp pelvic pain.
Hemorrhagic rupture: If cyst contains blood, rupture can cause internal bleeding with lightheadedness, fainting, rapid heart rate. Requires emergency evaluation.
How They're Typically Evaluated
Pelvic Ultrasoundβββ
Transvaginal ultrasound is the primary imaging modality. Differentiates simple vs. complex cysts and assesses size and characteristics.
Simple cysts: Thin-walled, fluid-filled, no solid components. Usually benign functional cysts.
Complex cysts: Thick walls, septations, solid components, or irregular appearance. Require further evaluation.
Follow-Up Ultrasound
For simple functional cysts, repeat ultrasound in 4-12 weeks confirms resolution. Most functional cysts disappear within 1-3 menstrual cycles without treatment.
CA-125 Blood Test
Tumor marker that can be elevated in ovarian cancer. However, also elevated in benign conditions (endometriosis, fibroids, PID). More useful in postmenopausal women. Not a reliable cancer screening test in premenopausal women.
Treatment Options
Functional Cysts: Observation (Watchful Waiting)βββ
For simple cysts less than 5 cm: Expectant management is appropriate. Most resolve spontaneously within 1-3 menstrual cycles.
- β’ Repeat ultrasound to confirm resolution
- β’ Hormonal contraceptives may be considered to prevent recurrence (they don't shrink existing cysts but may prevent new ones)
Indications for Surgery
Surgery may be recommended for:
- β’ Cysts larger than 5-10 cm (size threshold varies)
- β’ Complex appearance suspicious for malignancy
- β’ Cysts persistent beyond 3 menstrual cycles
- β’ Causing significant symptoms
- β’ Any cyst in a postmenopausal woman (functional cysts should not occur after menopause)
- β’ Suspected torsion or rupture (emergency)
When to Seek Medical Care
Emergency (Call 911/ER)
- β’ Sudden, severe pelvic pain (one-sided)
- β’ Pain with nausea, vomiting, fever
- β’ Lightheadedness, fainting, rapid heart rate
Urgent (24-48 hours)
- β’ New, persistent pelvic pain
- β’ Worsening pain with intercourse
- β’ Abdominal bloating that doesn't resolve
Routine Appointment
- β’ Known cyst on ultrasound (follow-up)
- β’ Mild, intermittent pelvic discomfort
- β’ Irregular periods with pelvic pain
Key Reassurance Points
- Most ovarian cysts are functional and resolve spontaneously within 1-3 cycles without treatment.
- Functional cysts are part of normal ovulation, not a disease or abnormality.
- Cancer is rare in premenopausal women with simple cysts. Simple, small cysts in reproductive-age women are almost always benign.
- Observation is appropriate for simple cysts. Not every cyst requires surgery or even treatment.
What This Page Does NOT Replace
This educational content cannot and does not:
- β’ Diagnose your cyst type or assess malignancy risk
- β’ Interpret your ultrasound findings
- β’ Determine whether you need surgery
- β’ Provide treatment recommendations specific to your situation
- β’ Replace clinical evaluation and shared decision-making with your healthcare provider
Cyst management requires individualized assessment based on your age, symptoms, cyst characteristics, and personal health history.
Key Takeaways
- Ovarian cysts are extremely common and most are functional, benign, and asymptomatic
- Most functional cysts resolve spontaneously within 1-3 menstrual cycles
- Ovarian torsion and hemorrhagic rupture are rare but require emergency evaluation
- Transvaginal ultrasound is the primary tool for distinguishing simple from complex cysts
- Cancer is rare in premenopausal women with simple, small cysts
- Observation is appropriate for simple cysts under 5 cm; surgery is reserved for specific indications
Related Resources
Endometriosis
Endometriomas (chocolate cysts) are a type of ovarian cyst caused by endometriosis
Read More βEvidence Summary
Well-Established (βββ)
Natural history of functional cysts, transvaginal ultrasound as first-line imaging, low malignancy risk in premenopausal women with simple cysts, ovarian torsion as a surgical emergency
Emerging Evidence (ββ)
Optimal size thresholds for surgical intervention, role of hormonal contraceptives in preventing recurrence, best follow-up intervals for complex but likely benign cysts
Research Gaps (β )
Best strategies to reduce unnecessary surgery for likely-benign complex cysts, CA-125 reliability across different patient populations, long-term outcomes after ovarian-sparing surgery for torsion
Last Updated: January 2025