US Pharm. 2016;41(9):13-14.

Fluid-Filled Sacs Within or on the Ovary

An ovarian cyst is a sac filled with fluid that forms inside or on the surface of an ovary. Ovarian cysts are common, especially during a woman’s childbearing years. Most ovarian cysts form at the time of ovulation and are known as functional cysts. These cysts are benign (that is, not cancerous). There are other types of ovarian cysts, but functional cysts are the most common. Depending on their size, ovarian cysts can cause symptoms. Functional ovarian cysts usually go away on their own, but in some cases surgical removal is necessary.

Ovarian Cysts Are Common, and Most Are Noncancerous

The ovaries are small, almond-shaped organs on either side of the uterus that contain tiny sacs of fluid called follicles. Each follicle contains an egg. During a woman’s monthly cycle, a follicle swells with a maturing egg, eventually breaking open to release the egg into the fallopian tube to be fertilized. Once the egg is released, the fluid-filled follicle dissolves. If the follicle does not rupture or release the egg, a follicular cyst (one type of functional cyst) may form. The other type of functional cyst, a corpus luteum cyst, forms after the egg is released if the follicle seals off and fluid accumulates. There are other types of ovarian cysts, including endometriomas, cystadenomas, and dermoid and polycystic ovary syndrome (PCOS)–related cysts.

Symptoms and Diagnosis of Ovarian Cysts

Small cysts may not cause any symptoms, but larger cysts can cause pelvic and back pain, bloating, irregular periods, constipation, and painful intercourse.

An ovarian cyst may be discovered during a routine gynecologic examination or when a woman with symptoms visits a healthcare provider. A sonogram may be performed to better examine the cyst and help the doctor select the best treatment. If appropriate, a blood test for cancer antigen 125 protein may be useful to help determine whether the cyst is cancerous.

Treatment of Ovarian Cysts

The treatment of ovarian cysts depends on a woman’s age, the presence or absence of symptoms, any coexisting conditions related to ovarian cysts, and the appearance of the cyst on the sonogram.

Small functional cysts that cause few symptoms are monitored for several months to ensure that they disappear without treatment. Birth control pills or other hormone supplements may be prescribed to prevent the future formation of functional cysts.

Benign ovarian cysts also may form as a result of other conditions, such as endometriosis or PCOS. Endometriomas sometimes develop in women with endometriosis, which is the growth of uterine-lining tissue in areas outside the uterus. An endometrioma is usually treated with hormones to shrink the endometrial tissue or surgery to remove the cyst. PCOS involves the formation of benign ovarian cysts and multiple symptoms caused by an excess of androgen (a male sex hormone). Common symptoms of PCOS include pelvic pain; excess hair growth on the face, chest, or stomach; acne and oily skin; and infertility. Treatment of PCOS includes hormones and other medications that help reverse the effects of excess androgen in these patients.

Complications of Ovarian Cysts

The primary complication of a noncancerous cyst occurs when the cyst becomes twisted or ruptures. This serious situation requires immediate medical attention. Sudden and severe pelvic or abdominal pain; fever and chills; vomiting; or weakness, dizziness, and rapid breathing all signal a twisted or ruptured ovarian cyst.

Functional cysts do not affect fertility. Ovarian cysts that occur as part of PCOS and those resulting from endometriosis can cause fertility problems.

Benign ovarian cysts are very common. Ovarian cysts that are cancerous are relatively rare, representing less than 2% of all new cancer cases, about 20,000 cases each year. Cancerous ovarian cysts are most often found in women, primarily postmenopausal, older than 55 years of age.

Ovarian cysts are less common after menopause. If a postmenopausal woman experiences the symptoms of ovarian cysts, it is important for her to be evaluated by a healthcare professional.