Other conditions that may have symptoms similar to ovarian cysts include:

• Infection of the appendix (appendicitis).
• Pregnancy involving the fallopian tube (ectopic pregnancy).
• Endometrial tissue found outside of the uterus (endometriosis). When this tissue grows on an ovary, it is called an endometrioma.
• Ongoing (chronic) inflammation of the intestines (inflammatory bowel disease).
• Digestive problems, such as irritable bowel syndrome.
• Formation of crystals in the urinary system (kidney stones).
• Twisting of the ovary on its supporting ligament (ovarian torsion).
• Inflammation or infection of the female pelvic organs (pelvic inflammatory disease, or PID).
• Enlargement of and cyst formation in the ovaries (polycystic ovary syndrome, or PCOS). But PCOS is a multisystem condition that also causes irregular menstrual cycles, weight gain, acne, excess hair growth, and insulin problems. Also, the cysts present in PCOS are usually less than 1.5 in. (3.8 cm) in diameter, smaller than is usually found in functional ovarian cysts.

Ovarian cancer often causes no symptoms, though early signs can include weight loss, weight gain, increased abdominal girth, gas, and bloating.