Cervical cysts aren't cancerous. The most common variety is a nabothian (nuh-BOW-thee-un) cyst, which forms when normal tissue on the outer part of the cervix grows over the glandular, mucus-producing tissue of the inner part of the cervix. When mucus, fluid or tissue becomes trapped, a cyst forms.
Nabothian cysts are so common that they're considered to be a normal feature of cervical anatomy. Your doctor might discover one incidentally during a pelvic exam. In general, cervical cysts don't cause symptoms and require no treatment.
Your doctor might collect a tissue sample (biopsy) to send for lab testing if a cervical cyst or other lesion looks unusual. Other concerns include abnormal vaginal bleeding, pelvic pain or pain during sex.