An ovarian cyst of 3.7 centimeters is relatively not serious because this ovarian cyst is relatively small at the moment. Ovarian cysts can be divided into two types, namely physiological ovarian cysts and pathologic ovarian cysts, which have a relatively small chance of developing into malignant lesions, so they are not serious. 1. Physiological ovarian cysts: physiological ovarian cysts usually appear after ovulation and will disappear naturally after menstruation, which is a physiological phenomenon and does not need to be treated. Now we find that there is an ovarian cyst of 3.7 centimeters, it is recommended to check again after the next menstrual period, if this ovarian cyst disappears, it means that it is a physiological ovarian cyst. 2. Pathological ovarian cysts: if the ovarian cyst still exists after the next menstrual period, it means that it is a pathological ovarian cyst, and the most common one is ovarian chocolate cyst. At present, this ovarian cyst is only 3.7 centimeters, which is still relatively small, and it can be left untreated, but it should be reviewed by ultrasound on a regular basis.