Ovarian cysts are fluid-filled sacs that can develop on or within an ovary. They are common, with many women experiencing them, especially during their childbearing years. Most ovarian cysts are harmless and resolve without medical intervention.
Understanding Ovarian Cyst Growth
The growth pattern of an ovarian cyst varies significantly by type. Functional cysts, the most common type, form as part of the normal menstrual cycle, including follicular cysts (when a follicle doesn’t release its egg) and corpus luteum cysts (when fluid accumulates after egg release). Functional cysts grow quickly, reaching about 2-3 centimeters in days to weeks, and rarely exceed 5 centimeters. They often resolve within one to three menstrual cycles as hormonal levels fluctuate.
Other types of cysts, known as pathological cysts, arise from abnormal cell growth and do not resolve spontaneously. Dermoid cysts grow very slowly, averaging about 1.8 millimeters per year, and can exist for years without symptoms. Endometriomas, often called chocolate cysts, are associated with endometriosis and expand gradually with each menstrual cycle, growing a few millimeters annually. Cystadenomas, which develop from the surface tissue of the ovary, have variable growth rates; some remain small for years, while others can grow quite large, occasionally exceeding 10 centimeters.
Factors Influencing Growth Rate
Beyond cyst type, several factors influence how quickly an ovarian cyst might grow. Hormonal fluctuations play a significant role, tied to the menstrual cycle in functional cysts. Pregnancy and certain fertility medications can also impact cyst development and growth, sometimes leading to multiple follicles or cysts.
Age is another important factor, with younger women in their childbearing years more prone to functional cysts due to active ovulation. Postmenopausal women, who no longer ovulate, rarely develop functional cysts; therefore, any cyst appearing after menopause warrants prompt evaluation. Underlying medical conditions, such as polycystic ovary syndrome (PCOS) or endometriosis, can also affect cyst formation and growth patterns. PCOS involves multiple small, immature follicles, while endometriosis can lead to endometriomas that grow progressively.
Recognizing and Monitoring Growth
Symptoms may suggest a growing ovarian cyst, though many cysts cause no symptoms at all. Symptoms may include pelvic pain or pressure, bloating, or changes in bowel or bladder habits such as frequent urination. Sudden, severe pelvic pain, with nausea or vomiting, can indicate a complication like a ruptured cyst or ovarian torsion.
Medical professionals primarily monitor ovarian cyst growth using imaging techniques. Transvaginal or abdominal ultrasound is the most common method, assessing the cyst’s size, location, and characteristics. Repeat ultrasounds track changes in size over time. While blood tests, such as CA-125, may be used with imaging, they primarily assess malignancy risk, especially in postmenopausal women or with concerning features, rather than monitoring growth rate.
When Rapid Growth is a Concern
Rapid or significant growth of an ovarian cyst is a medical concern. While functional cysts develop quickly, they resolve. However, a cyst that doubles in size over a short period warrants further investigation. Cysts reaching a large size (over 5-10 centimeters) or those that persist over several menstrual cycles, particularly if not functional, may also raise concerns.
Certain features observed on imaging, such as solid components, irregular borders, or increased blood flow within the cyst, indicate closer evaluation. Rapid growth or a large size increases the risk of complications like ovarian torsion (where the ovary twists, cutting off blood supply) or cyst rupture, which can cause severe pain and internal bleeding. These situations require prompt medical attention to prevent damage to the ovary or address acute symptoms.