Ovarian Cysts: When They're Normal and When They're Not
An ovarian cyst is simply a fluid-filled sac on or in the ovary, and the large majority are "functional" cysts — a normal part of the ovulation process, not a disease process at all. Most are found incidentally, on imaging done for another reason, and resolve without any treatment.
Last updated August 2026
Functional cysts are usually just normal ovulation
Follicular cysts (a follicle that didn't release an egg and kept growing) and corpus luteum cysts (the structure left behind after ovulation, which sometimes fills with fluid or blood instead of breaking down normally) are the two functional types, and they form to some degree essentially every cycle. Most resolve within 4-8 weeks without treatment, which is why a repeat ultrasound rather than immediate intervention is often the first move.
Other types are less common, but worth knowing
Dermoid cysts (mature teratomas) contain tissue like hair, skin, or fat and don't resolve on their own. Endometriomas ("chocolate cysts") form when endometriosis tissue implants on the ovary and are a marker of endometriosis specifically. Cystadenomas are benign growths from ovarian surface tissue that can grow fairly large. None of these are functional cysts, and none are expected to resolve without treatment the way functional cysts do.
Symptoms — and why most cysts have none
Most cysts cause no symptoms and are found incidentally. When there are symptoms, they're usually pelvic pain, bloating, or a sense of pressure — often on one side, and sometimes worse around ovulation or with intercourse.
When it's an emergency
Sudden, severe one-sided pelvic pain with nausea or vomiting can mean ovarian torsion — the ovary twisting on its own blood supply — which needs immediate evaluation to try to save the ovary. Sudden severe pain alongside signs of heavy internal bleeding (lightheadedness, rapid heartbeat) can mean a ruptured cyst bleeding significantly. Either picture is a same-day, not "wait and see," situation.
How size and appearance guide the plan
Ultrasound description matters a lot: "simple" (a clear, fluid-filled, thin-walled cyst) is reassuring and usually just monitored; "complex" (solid components, irregular walls, internal septations) prompts closer follow-up or further imaging. Size thresholds guide how closely something is followed. Postmenopausal cysts get more scrutiny than premenopausal ones by default, since the underlying risk calculus is different after menopause — a simple small cyst is still usually low-risk, but the threshold for follow-up tends to be tighter.
When surgery is considered
Persistent or growing cysts, ones with complex features, symptomatic cysts significantly affecting quality of life, or postmenopausal cysts with any concerning features are the situations where surgical removal is typically discussed — not simple functional cysts found once and never seen again.
Worth discussing with your provider
Educational information only — general patterns that vary by person. This is not medical advice, a diagnosis, or a substitute for care from your own clinician.
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