Ovarian cysts: types, symptoms and treatment

Author: Josephine Cabrall
Fertility Specialist Naturopath | BHSc(NAT) | NHAA

Last reviewed: June 23, 2026

An ovarian cyst is a fluid-filled sac that forms in or on an ovary. The reassuring headline first: most ovarian cysts are benign (non-cancerous), cause no symptoms at all, and clear up on their own within a few menstrual cycles.^2,3 Some grow larger, become painful, or need removing, and a few turn out to be something else entirely, but the great majority come and go quietly, often without you ever knowing they were there.

Cysts can develop at any life stage, from before birth right through to after menopause, in women and people with vaginas.¹ Occasionally, what looks like a painful ovarian cyst turns out to be a different problem on investigation, such as an ectopic pregnancy, ovarian torsion (a twisted ovary) or appendicitis.

In our clinic, we regularly reassure people who have had a cyst picked up by chance on a scan done for something else. Most need nothing more than a repeat scan a few weeks later to confirm it has gone.

Symptoms of ovarian cysts

Most cysts cause no symptoms and are found by accident. When they do cause trouble, it tends to be pressure or pain in the lower abdomen. Possible signs include:

Pain or discomfort low in the abdomen, often dull and on one side
A feeling of fullness, bloating or pressure
Pain during sex, especially with deep penetration (dyspareunia)
Needing to wee more often, from pressure on the bladder
Difficulty emptying the bowel, or a constant urge to go
An irregular menstrual cycle or abnormal vaginal bleeding
Feeling full quickly when eating, indigestion or heartburn
In children, signs of early puberty (precocious puberty)

When to get urgent help

Two situations turn an ovarian cyst into an emergency: a cyst that bursts (rupture) and a cyst that twists the ovary and cuts off its blood supply (ovarian torsion). Both are more likely with larger cysts, usually above about 5 cm (around 2 inches, roughly the size of a golf ball).³

Seek urgent medical care, or go to your nearest emergency department, if you have:

Sudden, severe pain low in the abdomen or pelvis, often on one side
Pain with nausea, vomiting or a fever
Feeling faint, dizzy or light-headed, or breathing rapidly
A racing heartbeat with cold, clammy skin

A twisted ovary needs rapid surgery to save it, so this is not a time to wait and see. If you already know you have a cyst and the pain changes suddenly, get it checked.

Why do ovarian cysts develop?

Most cysts are simply part of the normal monthly cycle, where the ovary grows and releases an egg. A few develop because of an underlying condition or hormonal change. Either way, the great majority are benign and resolve without any treatment.^2,3

Types of ovarian cysts

Functional cysts

These are by far the most common cysts and come straight from your normal menstrual cycle. They are almost always harmless and usually disappear on their own.³

Follicular cysts

Each cycle, your ovaries grow small sacs called follicles, each holding an egg. Normally one follicle swells and bursts to release its egg at ovulation. If a follicle keeps growing without releasing the egg, it becomes a follicular cyst. These are often larger than about 2.5 cm (roughly an inch, about the size of a grape) and can bring a sense of heaviness or discomfort.

Corpus luteum cysts

After ovulation, the empty follicle becomes a structure called the corpus luteum. If it does not break down as it should and instead seals over and fills with fluid, it forms a corpus luteum cyst, sometimes growing to around 3 cm (a little over an inch). These can cause a dull, one-sided ache and occasionally bleed if they rupture.

Haemorrhagic cysts

A haemorrhagic cyst is a functional cyst that bleeds inside itself when a small blood vessel in its wall breaks. The trapped blood makes the cyst swell and can cause sudden one-sided pain. Most settle on their own, but a larger one can rupture and spill blood into the abdomen, which is one of the situations that needs urgent review.

Less common cysts

Theca-lutein cysts

Theca-lutein cysts form when part of the ovary is over-stimulated by the pregnancy hormone human chorionic gonadotropin (hCG). They tend to appear in pregnancy or the second half of the cycle, often on both ovaries, and can cause pelvic pain and swelling. They may twist, bleed or burst, but can also clear up by themselves.

Luteoma of pregnancy

A solid, benign overgrowth of hormone-producing ovarian tissue that appears in pregnancy. It can make androgens (male-type hormones) and usually shrinks away on its own after the birth.

Dermoid cysts

A dermoid cyst (a type of teratoma) is a sac that grows from the egg-making cells of the ovary, so it can contain odd tissues such as hair, skin, fat, teeth and even thyroid tissue. It is usually benign but is counted as a tumour rather than a functional cyst, and is often removed.

Teratomas

A teratoma is a germ-cell growth containing the three embryonic tissue layers (ectoderm, endoderm and mesoderm). Dermoid cysts are the most common, benign kind; rarer forms can be malignant.

Neoplastic cysts

Here a group of cells grows unexpectedly within the ovary. These can be benign or, less often, malignant, which is why a cyst with unusual features on a scan is investigated further.

Cysts linked to other conditions

Endometriomas (chocolate cysts)

Endometriomas are blood-filled cysts that form from misplaced womb-lining tissue and are linked to endometriosis. They can cause intense pain or none at all.

Polycystic ovaries (PCOS)

In polycystic ovarian syndrome (PCOS), the ovaries hold many small follicle-like sacs because of a hormonal imbalance involving androgens. These are smaller than other ovarian cysts and do not themselves cause pain, though having PCOS can make you more prone to other cyst types.

Risk factors for ovarian cysts

Fertility treatment that stimulates the ovaries (ovulation induction)
Pregnancy, especially around the mid-pregnancy peak in hCG
An underactive thyroid (hypothyroidism), which in severe untreated cases can drive very large cysts that shrink once the thyroid is treated⁵
The breast-cancer medicine tamoxifen
Smoking
A high body mass index (BMI)
Cysts present before birth, driven by hormones crossing from the mother⁶

Risk factors for a cancerous cyst

Cancer is uncommon, but the risk is a little higher with:

A family history of ovarian or breast cancer
Older age, particularly after menopause
A personal history of breast cancer
BRCA gene changes
Never having been pregnant, or infertility

How ovarian cysts are diagnosed

An ultrasound is the main test, usually through the vagina (transvaginal) for a close-up view. It shows the size of a cyst and whether it looks simple (just fluid) or complex (solid parts, walls or blood), which guides what happens next.⁷

A pregnancy test, urine test and swabs may be done to rule out other causes of pelvic pain. In some cases a blood test such as CA-125 is used, though it can be raised by many harmless conditions and is interpreted with care, particularly before menopause.

Treatment of ovarian cysts

Most ovarian cysts need no treatment at all and are simply watched with a repeat scan to confirm they have gone. Going on the contraceptive pill can lower the chance of forming new functional cysts, but it does not make an existing cyst clear up any faster, so the pill is not a treatment for a cyst you already have.⁸

Surgery is considered for cysts that are large, complex, persistent or causing symptoms, typically those bigger than about 5 to 10 cm (roughly 2 to 4 inches, a golf ball to a tennis ball).⁹ Even very large cysts can often be removed with keyhole (laparoscopic) surgery rather than open surgery.⁹ Occasionally one or both ovaries are removed (oophorectomy), and in postmenopausal women a hysterectomy may be suggested where cancer is a concern.

Where the ovary itself is healthy, surgeons aim to remove only the cyst and preserve the ovary, because surgery carries its own risk to future fertility and ovarian reserve. In fact, for cysts and fertility, the operation can sometimes do more harm than the cyst.⁴ In our experience, this is worth raising with your specialist if you hope to conceive.

What else could it be?

Several other conditions can mimic an ovarian cyst on a scan or cause similar pain, including:

A urethral diverticulum, paraovarian cyst (next to the ovary) or peritoneal cyst
A fluid-blocked fallopian tube (hydrosalpinx) or inflamed tubes (salpingitis)
A tubo-ovarian or abdominal abscess, or pelvic inflammatory disease
A fibroid (pedunculated leiomyoma)
Ectopic pregnancy or possible miscarriage
Appendicitis, diverticular disease, inflammatory bowel disease or bowel obstruction
Kidney problems: stones, a pelvic kidney, or water on the kidney (hydronephrosis)
A twisted ovary (ovarian torsion), ovarian cancer or endometriosis

Frequently asked questions

Are ovarian cysts dangerous?

Usually not. The large majority are benign and resolve on their own.^2,3 The main risks are a cyst bursting or twisting the ovary, which cause sudden severe pain and need urgent care.

Will an ovarian cyst go away on its own?

Functional cysts, the most common type, usually clear up within two or three menstrual cycles without treatment.^3,8 A repeat scan is often used to confirm it has gone.

Can ovarian cysts affect my fertility?

Most do not. Some cyst types linked to conditions like endometriosis or PCOS can play a role, but surgery to remove a cyst can itself affect ovarian reserve, so it is weighed up carefully.⁴

Can I get an ovarian cyst after menopause?

Yes. Cysts are less common after menopause but still occur, and because the cancer risk is slightly higher at this stage they are usually monitored or investigated more closely.³

Does the pill get rid of ovarian cysts?

No. The pill can reduce the chance of forming new functional cysts, but it does not speed up the disappearance of a cyst you already have.⁸

What size cyst needs surgery?

There is no single cut-off, but cysts larger than about 5 to 10 cm (2 to 4 inches), or those that are complex, persistent or symptomatic, are more likely to be removed.⁹ Many can be taken out with keyhole surgery.

What to do next

If a cyst has been found on a scan and you have no symptoms, the usual next step is simple watchful waiting with a follow-up scan. If you have ongoing pelvic pain, changes to your cycle, or pain during sex, it is worth booking a proper assessment so the cause can be pinned down.

For sudden severe pain, vomiting, fever or feeling faint, treat it as an emergency and get seen straight away.

Not sure where your symptoms fit? Ask Aunt Vadge’s Assistant using the chat widget at the bottom left of your screen, or book in with one of our practitioners for a personalised look at what is going on.

This article is general information and is not a substitute for personalised medical advice. If you are worried about a cyst or have new or severe pelvic pain, please see a clinician.