How Do You Get Ovarian Cysts? Step By Step

Ovarian cysts form when a follicle in the ovary fails to rupture and release its egg, or when the follicle reseals after releasing the egg and fills with fluid. Most cysts are functional — they are part of the normal menstrual cycle and resolve on their own. The step-by-step process starts with hormonal signaling from the brain to the ovary, continues through follicle growth, and ends either in ovulation or in a cyst that forms when that process goes off-script.

How Do U Get Ovarian Cysts? The Step-By-Step Process

Every menstrual cycle, your brain sends a hormone signal to your ovaries to start maturing an egg. That signal is follicle-stimulating hormone, or FSH, released from the pituitary gland. The ovary responds by growing a small sac called a follicle around the egg.

As the follicle grows, it produces estrogen. When estrogen reaches a certain level, the brain releases a surge of luteinizing hormone (LH). That surge is what triggers ovulation — the follicle ruptures and releases the egg.

Here is where cysts begin. Two things can go wrong at this stage:

• The follicle keeps growing but never ruptures. The egg is never released. Fluid builds up inside, and the structure becomes a follicular cyst.
• The follicle ruptures and releases the egg, but then the opening seals shut. The empty sac fills with fluid or blood and becomes a corpus luteum cyst.

Both are called functional cysts because they arise from the normal function of ovulation. They are the most common type of ovarian cyst, especially in women who are still menstruating.

What Actually Triggers a Cyst to Form?

A cyst forms when the balance of hormones that controls ovulation is disrupted. The hypothalamus, pituitary gland, and ovary communicate in a loop. When that loop misfires, the follicle can fail to rupture on schedule.

Several things can disturb that loop:

• Hormonal fluctuations around puberty and perimenopause, when cycle signaling is less predictable.
• Fertility medications that stimulate the ovaries to grow multiple follicles at once. These raise the risk of both cysts and, in some cases, ovarian hyperstimulation syndrome.
• Conditions that affect ovulation, such as polycystic ovary syndrome (PCOS), where follicles accumulate because ovulation does not occur regularly.
• Pregnancy, where the corpus luteum stays active longer than usual to support the pregnancy and can enlarge into a cyst.

Most functional cysts are not caused by anything a woman did or did not do. They are a byproduct of the ovulation machinery itself.

What Are the Different Types of Ovarian Cysts?

Not all ovarian cysts come from ovulation. Some grow from the tissue of the ovary itself, and these behave differently. Knowing the type matters because it affects what happens next.

Dermoid cysts, endometriomas, and cystadenomas are not functional. They do not follow the ovulation cycle and generally do not resolve with time the way functional cysts do.

What Does an Ovarian Cyst Feel Like?

Most ovarian cysts cause no symptoms at all. Many are found by chance during a pelvic exam or ultrasound done for another reason. When symptoms do occur, they tend to be mild.

Common symptoms include:

• Pelvic pain or a dull ache on one side
• Bloating or a feeling of fullness in the lower abdomen
• Pain during intercourse
• Changes in bowel habits or urination if a cyst presses on nearby organs
• Irregular periods, though this is more common with hormone-producing cysts

Sudden, severe pelvic pain — especially with nausea, vomiting, or fever — is different. It can signal a cyst that has ruptured or twisted the ovary, which is a medical emergency. Ovarian torsion cuts off blood flow to the ovary and needs urgent treatment.

When Should You Be Concerned About a Cyst?

The vast majority of ovarian cysts are benign. Functional cysts, in particular, are a normal part of many women’s cycles. The concern is not the cyst itself but whether it has features that suggest something else.

Certain characteristics on ultrasound raise the level of attention. These include cysts that are solid rather than fluid-filled, have thick or irregular walls, contain internal partitions, or are accompanied by free fluid in the abdomen. A cyst that keeps growing or does not resolve over several cycles also warrants a closer look.

Age matters too. Ovarian cancer is uncommon in younger women, but the risk rises after menopause. A new cyst in a postmenopausal woman is evaluated differently than one in a woman of reproductive age. This does not mean every postmenopausal cyst is cancer — most are not — but the threshold for further testing is lower.

Blood tests such as CA-125 can be part of an evaluation, but CA-125 is not a screening test for ovarian cancer and can be elevated by many non-cancerous conditions, including endometriosis, fibroids, and even menstruation. It is one piece of information, not a diagnosis.

How Are Ovarian Cysts Diagnosed?

Diagnosis usually starts with a pelvic exam and an ultrasound. Ultrasound is the main imaging tool because it shows whether a cyst is fluid-filled or solid, its size, and its structure. Transvaginal ultrasound gives a clearer view of the ovaries than an abdominal ultrasound.

For simple, fluid-filled cysts in women of reproductive age, the common approach is watchful waiting. A repeat ultrasound in a few weeks or months can show whether the cyst has resolved. Many functional cysts disappear within one to three menstrual cycles.

If a cyst looks complex, is large, or persists, a doctor may recommend further imaging such as an MRI, or surgery to remove and examine the tissue. The decision depends on the cyst’s appearance, the woman’s age, symptoms, and whether she has a family history of ovarian or breast cancer.

Do Ovarian Cysts Affect Fertility?

Most functional cysts do not affect fertility. They are a sign that ovulation is happening, not that it is failing. A follicular or corpus luteum cyst typically resolves without treatment and leaves fertility intact.

The picture is different for conditions that cause cysts as a feature. PCOS involves many small follicles that do not mature and ovulate regularly, and it is a common cause of infertility. Endometriomas are linked to endometriosis, which can affect fertility through scarring and inflammation. In these cases, the cyst is part of a broader condition, and that condition — not the cyst alone — is what affects fertility.

Surgery to remove a cyst can, in some cases, remove healthy ovarian tissue along with it. That is one reason doctors weigh surgical decisions carefully in women who want to preserve fertility.

Can You Prevent Ovarian Cysts?

There is no reliable way to prevent functional ovarian cysts. They arise from normal ovulation, and as long as a woman is ovulating, the possibility exists.

Hormonal birth control is sometimes prescribed to suppress ovulation, which prevents new functional cysts from forming. The evidence that this reduces cyst formation in women without a diagnosed condition is limited, and it does not shrink cysts that already exist. Some clinicians prescribe it for women who form cysts repeatedly, but this is a clinical judgment rather than a proven prevention strategy for everyone.

For cysts caused by PCOS or other ovulatory conditions, managing the underlying condition is the more meaningful approach. Regular checkups and imaging when symptoms appear are the practical steps most women can take.