Overview of Ovarian Cysts

Ovarian cysts are most common in the childbearing years

Doctor talking to patient about ovarian cysts
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An ovarian cyst is a fluid-filled sac that grows on or inside the ovary and may be discovered by your doctor during a routine pelvic examination. Ovarian cysts are common, especially in women during their reproductive years, and generally cause little to no pain, unless a complication develops.

Functional cysts are the most common type of ovarian cyst and are associated with a woman's menstrual cycle. There are two types of functional cysts:

  • Follicular Cyst
  • Corpus Luteum Cyst

Follicular Cysts

Follicular cysts are the most common type of cysts in premenopausal women. They are best diagnosed with an ultrasound and appear to have thin walls and be fluid-filled. Follicular cysts can range widely in size but are usually small (less than 3cm in diameter), although they can grow to as large as 10cm in diameter (the size of a grapefruit).

How do follicular cysts develop? Normally, a follicle ruptures and releases an egg during ovulation. But when rupture does not occur, the follicle can continue to grow and form a cyst that is filled with fluid or blood.

What are the most common symptoms of follicular cysts? Some women experience a dull or sharp discomfort or pressure in their lower abdomen with follicular cysts, especially during sex or when having a bowel movement.

That being said, most women do not experience symptoms with follicular cysts, unless they burst open, bleed, or a serious condition called ovarian torsion develops (twisting of the ovary on its own blood supply). These complications generally cause severe, sharp, and sudden lower abdominal pain and require immediate medical attention. Ovarian torsion may also be associated with nausea and vomiting. 

How are follicular cysts treated? The truth is that if you wait, almost all ovarian follicular cysts will just go away on their own, usually within three to four weeks, but sometimes it takes months. If your doctor finds a cyst, she may recommend a repeat ultrasound in about 6 to 8 weeks to ensure it is not enlarging.

The good news is that surgery is rarely needed to treat a follicular cyst—mostly if a follicular cyst is enlarging or causing symptoms like persistent discomfort.

Surgery and a blood test called CA 125 may be recommended if you are postmenopausal and have a cyst, as this is not as common. High blood levels of CA 125 can indicate ovarian cancer in a postmenopausal woman.

Do birth control pills help treat functional follicular cysts? The short answer is no. They only help prevent future cysts from forming. They will not make your current cysts go away.

What happens if the cyst does not go away? While your doctor can take a good professional educated guess, there is no way to know for sure if the persistent ovarian cyst is a physiologic cyst or an ovarian tumor. There are some pretty good signs, though, that you have a cyst rather than a tumor. Of course, you do not want to miss the boat and be treating a “tumor” with natural means that will never work. You can even risk your life or at least cause a bigger surgery if you delay—so it’s very important to know which it is under the care of your doctor. 

Corpus Luteum Cyst

Another type of functional cyst is known as a corpus luteum cyst (CLC). These are less frequent than a follicular cyst, but like follicular cysts generally cause no symptoms unless they bleed, burst, or ovarian torsion occurs. They also usually resolve on their own within a few weeks (sometimes months).

How do corpus luteum cysts develop? Normally, after a follicle releases an egg it begins producing progesterone and becomes a corpus luteum. If the egg is not fertilized by sperm, the corpus luteum will disappear. If a pregnancy does not occur and the corpus luteum does not disappear, it can fill with fluid and blood and form a cyst. 

During early pregnancy, a corpus luteum cyst always forms. It usually goes away by the second trimester, though. Some do not, and if they do not look suspicious on the ultrasound, it is safe to leave them alone. In most cases, they eventually go away after pregnancy.

What are the symptoms of a corpus luteum cyst? A missed period followed by some spotting, one-sided pelvic pain, and a pelvic examination, which finds a tender ovarian mass, suggest that a persistent CLC is a likely culprit. That being said, like a follicular cyst, some women have no symptoms at all. 

In addition, with the above symptoms, it is important to make sure, that a pregnancy test is ordered, as these same findings may be there for an ectopic pregnancy (tubal pregnancy). An ultrasound may not be able to tell these two apart and the treatment would be completely different.

There is also a non-functional cyst, which can cause similar symptoms, called an endometrioma. An endometrioma arises from tissue that lines the uterus and is treated in yet another way, often involving surgery.

How are corpus luteum cysts treated? Like follicular cysts, these cysts usually go away on their own. If surgery is necessary because of bleeding, it is often possible to do it through a laparoscope (bandaid surgery). Usually, the ovary does not have to be removed. Only the cyst is removed and the bleeding is stopped.
If the cyst is NOT ruptured, and there is no bleeding or torsion, it is reasonable to avoid surgery and “wait it out." Why? A surgery, no matter how small, causes scars or adhesions to form. You want to avoid surgery if your doctor thinks it is safe based on all of the things you just read about.

Other Types of Ovarian Cysts

Besides functional cysts, there are other types of cysts like theca lutein cysts, which occur due to very high beta-hCG levels (the hormone of pregnancy). Theca lutein cysts are often seen with twins or molar pregnancies, where the placenta develops but the fetus does not. 

Polycystic ovary syndrome (PCOS) is a medical condition in women associated with obesity, hirsutism, acne, and irregular menstrual cycles. Some women with PCOS also have several (12 or more) small follicular cysts on their ovaries, which can be visualized with an ultrasound. That being said, a woman does not necessarily need cysts on her ovaries to be diagnosed with PCOS. 

A Word From Verywell

Finally, it is important to remember that pelvic pain with or without ovarian cysts being present does not mean the pain is coming from a gynecologic organ. In other words, there are other things down there in your pelvis. You could have appendicitis or other bowel problems, which have nothing to do with your gynecologic organs.

This all being said, be sure to see your doctor if you have any worrisome symptoms like new onset pain, fever, or nausea or have questions regarding a previously diagnosed ovarian cyst. 

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Article Sources
  • American College of Obstetrics and Gynecologists. (July 2015). Frequently Asked Questions: Ovarian cysts
  • Hochberg L, Hoffman MS. (August 2016). Differential diagnosis of the adnexal mass. In: UpToDate, Goff B, Garcia RL, Levine D (Ed), UpToDate, Waltham, MA.