The size of an ovarian cyst can vary depending on the type of cyst it is. Generally speaking, surgery isn’t recommended for ovarian cysts unless they’re large in size, cause symptoms, or are cancerous. Doctors may consider an ovarian cyst large if it measures 10 cm (about 4 inches) or greater. However, the size at which a cyst is considered dangerous can also depend on the type of cyst. For example, cysts caused by endometriosis need immediate surgery to prevent infertility in women.

According to different sources, an ovarian cyst larger than 5 cm is considered big and may be harmful. Cysts of more than 5 cm can be concerning, and any cyst larger than 5 cm may need surgery. In some cases, even the entire ovary might have to be removed. A cyst larger than 4 cm in diameter has a greater chance for torsion than those that are smaller.

It is important to note that smaller cysts are often considered normal and typically resolve on their own without causing significant issues. An ovarian cyst of size less than 4 cm is a variant of functional or follicular cysts. This size of cyst usually disappears on its own within 2 to 3 menstrual cycles.

In conclusion, the size of an ovarian cyst that is considered dangerous can vary depending on the type of cyst. However, generally, an ovarian cyst larger than 5 cm is considered big and may be harmful. If you have an ovarian cyst, it is important to consult a gynecological specialist who can differentiate between the different types of cysts and advise on the best course of action.