The first thing that one should learn about ovarian cysts is that it is a very general phenomenon. Follicles present in an ovary give out ovum or egg during the process of ovulation. But sometimes this ovulation is delayed and the follicle expands to form cystic structures filled with various secretions. Sometimes a corpus luteum develops into a cyst. Rupture of these cysts results in intense pain and internal bleeding. This condition can be treated with proper medication; and in majority of the cases a surgery is not required. Most of the ovarian cysts are functional cysts and they resolve automatically within 3 to 4 months. 
However, recurrence of symptoms and irregular menstrual cycles can be a big trouble hence proper medication and preventive measures are quite necessary.
Surgical intervention is suggested only if the cysts grows beyond a certain limit and causes severe symptoms. Most of the cysts that are small in size and they do not grow beyond 5 cm diameter. If proper rest and medication is administered these cysts can heal on its own and within a matter of weeks. Ovarian cysts occurring in middle-aged women do not create too many complications. However, if a cyst do not recede or rupture within 3 to 4 months, its surgical removal may be required. If these cysts are not removed within a certain time limit, they might eventually twist or burst causing serious damage. It can cause unbearable pain and might lead to various infections at a later stage. So, if you are having an ovarian cyst that is persistent in nature, its surgical resection is seriously recommended. Some people ignore such cases because the cyst might be showing hardly any symptoms but once it gets ruptured things become pretty complicated.
Simple cysts or functional cysts are not dangerous. They lead to pain and bleeding but once they are treated appropriately the patient is freed from all possible symptoms. But all the ovarian cysts are not simple in nature. Some cysts grow to cause complex problems and they are commonly known as complex cysts. Dermoid cyst is one such type of cyst which is a kind of teratoma. Teratoma is a tumor that is made up of different sorts of body cells like hair cell, bone cell etc. A dermoid cyst is filled with such materials and if it is not removed, it can grow and lead to malignant cancerous developments. Another form of complex ovarian cyst is known as endometrial cyst. This cyst contains endometrial tissue in it. Surgical removal of such complex cysts is necessary, if they cannot be controlled with medication.
