<P> Its rupture can create sharp, severe pain on the side of the ovary on which the cyst appears . This sharp pain (sometimes called mittelschmerz) occurs in the middle of the menstrual cycle, during ovulation . About a fourth of women with this type of cyst experience pain . </P> <P> Usually, these cysts produce no symptoms and disappear by themselves within a few months . </P> <P> This type can form when ovulation doesn't occur, and a follicle doesn't rupture or release its egg but instead grows until it becomes a cyst, or when a mature follicle involutes (collapses on itself). It usually forms during ovulation, and can grow to about 7 cm in diameter . It is thin - walled, lined by one or more layers of granulosa cell, and filled with clear fluid . </P> <P> Ultrasound is the primary tool used to document the follicular cyst . A pelvic exam will also aid in the diagnosis if the cyst is large enough to be seen . A doctor monitors these to make sure they disappear, and looks at treatment options if they do not . </P>

What is a collapsed follicle in an ovary
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