- Ovarian cysts are usually not painful and will go away on their own.
- However, if a cyst is growing or you have multiple cysts you may have symptoms and need surgery.
- A ruptured cyst can cause severe pain and vomiting and requires immediate medical aid.
- Visit Insider's Health Reference library for more advice.
Ovarian cysts are fluid-filled sacs that form inside or on the surface of an ovary. Some types of ovarian cysts — like those that form during a menstrual cycle — are common while others are less so.
Most cysts are benign and tend to go away on their own. You'll probably not even know you have a cyst.
However, if a cyst is large or continuously growing, it could lead to uncomfortable symptoms like pelvic pain or unusual vaginal bleeding.
Here are seven things that can cause an ovarian cyst and when you might need surgery.
1. Menstrual cycle
Functional cysts are a type of ovarian cyst that form during the menstrual cycle.
Each month, a follicle grows to release an egg. Cysts develop if the follicle doesn't break open to release the egg (follicle cyst) or it releases an egg but doesn't shrink (corpus luteum cyst).
Hormonal problems or drugs that help you ovulate may also cause functional cysts, but this type of cyst typically goes away on its own.
Sometimes these are painful, but the pain will also resolve with patience and time.
2. Polycystic ovary syndrome (PCOS)
PCOS, a hormonal disorder, can lead to the development of many small ovarian cysts. The cysts are generally harmless and do not need to be treated or surgically removed.
3. Pregnancy
A corpus luteum cyst normally forms in early pregnancy to support the baby, and it usually goes away by the second trimester.
If the cyst doesn't break down, it can cause symptoms like a pressure or dull ache in the abdomen, and it may have to be removed. However, surgery is rarely needed.
4. Infections
Severe pelvic infections can cause ovarian cysts if the infection spreads to the ovaries. You may need treatment depending on the type and size of the cyst.
5. Endometriosis
Endometriosis is a condition where tissue that is similar to what lines your uterus grows outside of the uterus instead of inside it.
That tissue can also attach to the ovary and form a growth, causing a cyst called endometrioma that occurs in 17% to 44% of people with endometriosis.
Symptoms and the appearance of the cyst on an ultrasound will clue your provider into whether or not it is an endometrioma.
6. Congenital condition
If skin layers don't form as they should during a baby's development in the uterus, a dermoid cyst can form anywhere on their body, including in or on an ovary, when they reach reproductive age.
A dermoid cyst is usually discovered during a pelvic exam or on an ultrasound. Your doctor may schedule regular ultrasound check-ups to keep an eye on it, or you may need it to be surgically removed.
This type of cyst can get large enough to move the ovary out of position, increasing the risk of ovarian torsion — a condition where the ovary is twisted around the tissues that support it — which requires emergency surgery.
7. Abnormal cell growth
Cysts caused by abnormal cell growth are all called pathological cysts, which include endometriomas, dermoid cysts, and cystadenomas — cysts that develop on the surface of an ovary.
"Cysts like dermoid or endometrioma will not go away on their own," says Farinaz Seifi, MD, FACOG, Yale Medicine gynecologic surgeon and assistant professor at Yale School of Medicine. They usually require surgical removal.
Cysts can also be cancerous and often have a characteristic appearance on ultrasound. Ovarian cysts in postmenopausal individuals require attention as the risk of cancer is higher. Blood tests, ultrasound, age of the patient and size of the cyst are factored into management decisions.
Ovarian cyst symptoms
Most ovarian cysts don't cause any symptoms because they are small. However, cysts aren't always straightforward.
"You might have a small and simple ovarian cyst but still feel abdominal pain or bloating. Alternatively, people may have larger cysts that are found incidentally on imaging, like an ultrasound or a CT scan," says Natasha Bhuyan, MD, family physician and regional medical director of the West Coast markets at One Medical Group.
If you do experience symptoms from an ovarian cyst it will typically manifest as one, or multiple, of the following symptoms:
- Pressure, bloating, or swelling in the lower abdomen
- Sharp or dull pain in the lower abdomen
- Unusual vaginal bleeding
- Dull ache in the lower back and thighs
- Pelvic pain
- Frequent urination
- Pain during intercourse
- Unexplained weight gain
If you think you have a cyst, get it checked out with your primary care provider so you can discuss potential treatment.
Treatment and prevention
Most cysts don't require treatment and will go away on their own within a few months.
If you frequently get functional cysts, you may be recommended to take hormonal birth control. Contraceptives can stop ovulation, which reduces the risk of future cysts, says Bhuyan. Although they don't necessarily treat functional cysts, they can prevent it from recurring.
Surgery may be needed if an ovarian cyst is large, continuously growing, painful, and continues through two or three menstrual cycles. If an infected or suspected cancerous cyst is not removed, the infection or potential disease may spread in the body.
Insider's takeaway
Many individuals might not be aware that they have a cyst unless it grows or causes symptoms. If you think you have a cyst, reach out to your health care provider for a diagnosis and potential treatment.
Severe symptoms such as sudden abdominal pain, fever and vomiting, faintness, and heavy vaginal bleeding may be a sign of a ruptured or infected cyst, which requires immediate medical care.
"Treatment really depends on the type of cyst, the size, and even your medical history, which is why it's good to have an ongoing relationship with a family physician or OB-GYN," says Bhuyan.