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What size of ovarian cyst is dangerous?

Andrew Bellingham

Andrew Bellingham

Pharmacist | 20+ Years | BPharm | Dip Clin Pharm

Ovarian cysts are fluid-filled sacs that can form on the ovaries. They’re very common, and usually do not cause any symptoms.

Virtually all women who still have a period, and 1 in 5 women who go through menopause will have one or more ovarian cysts without experiencing any symptoms. 

Ovarian cysts that cause symptoms are much less common, with only 1 in 25 women likely to be affected in their lifetime.

What size of ovarian cyst is dangerous in mm?

In general, most ovarian cysts smaller than 5 centimetres (50mm) in diameter are considered normal and typically resolve on their own without causing any issues. However, as cysts grow larger, they can potentially become more problematic.

Cysts larger than 5 centimetres are often monitored more closely by healthcare providers. While they may still be benign, larger cysts have an increased risk of complications such as rupture or torsion (twisting), which can cause severe pain and require medical intervention.

Moreover, cysts that continue to grow or persist over time may warrant further investigation to rule out the possibility of ovarian cancer, although it’s important to note that the majority of ovarian cysts are benign.

In rare cases, ovarian cysts can grow to an unusually large size, reaching several inches or even causing the ovary to become enlarged. These large cysts can exert pressure on surrounding organs, leading to symptoms such as abdominal pain, bloating, and difficulty urinating or having bowel movements.

Ultimately, the size of an ovarian cyst alone is not always a reliable indicator of its danger. Other factors, such as the type of cyst, its location, and whether it is causing symptoms, also play a significant role in determining the level of risk.

Frequently asked questions about ovarian cysts

How dangerous is an ovarian cyst?

Ovarian cysts are usually harmless, but large ones can cause complications like pain or rupture. Regular monitoring is essential.

When is ovarian cyst dangerous?

An ovarian cyst is considered dangerous if it causes severe pain, ruptures, or grows larger than 5 centimetres.

What is a large ovarian cyst size?

A large ovarian cyst is typically considered to be over 5 centimetres in diameter. However, size alone may not determine its danger; symptoms and other factors also matter.

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