A nabothian cyst is a small, harmless bump on the cervix filled with trapped mucus. These cysts are extremely common, often discovered incidentally during a routine pelvic exam, and almost never require treatment. Most range from a few millimeters to about 4 centimeters in diameter.
How Nabothian Cysts Form
Your cervix is lined with tiny glands that constantly produce mucus. Normally, this mucus flows freely. But sometimes a layer of flat skin cells (called squamous epithelium) grows over the top of these glands, essentially capping them shut. The glands keep producing mucus with nowhere for it to go, so it pools beneath the surface and forms a smooth, rounded cyst.
This process, called squamous metaplasia, happens naturally in a zone of the cervix where two types of tissue meet. It’s a normal part of cervical biology, not a sign of disease. Inflammation or physical trauma to the cervix, such as from childbirth, can accelerate the process by triggering extra tissue growth that blocks the glands. This is why nabothian cysts are particularly common in women who have given birth, though they can appear in anyone with a cervix at any age.
Symptoms You Might Notice
In most cases, you won’t notice anything at all. The vast majority of nabothian cysts are completely silent and only discovered when a healthcare provider spots them during a pelvic exam or Pap smear. They look like small, white or yellowish bumps on the cervix’s surface.
Rarely, a larger cyst or a cluster of multiple cysts can cause mild symptoms:
- Light pressure or fullness in the vagina
- Pain during intercourse
- Unusual discharge if a cyst ruptures, releasing mucus and small amounts of blood that may have an odor
A ruptured cyst isn’t dangerous. It simply means the trapped mucus has broken through the surface. The discharge usually resolves on its own within a short time.
How They’re Diagnosed
Most nabothian cysts are identified visually during a standard pelvic exam. They have a distinctive smooth, rounded appearance that’s easy for a provider to recognize. When imaging is needed, ultrasound can confirm the diagnosis. On ultrasound, they appear as well-defined, fluid-filled circles within the cervix. One study found cyst sizes ranging from 6 to 20 millimeters on imaging, with the majority being multiple rather than solitary. Some cysts sit near the outer opening of the cervix, while others form deeper inside.
In rare situations, particularly when cysts are unusually large or deep within the cervix, providers may want to rule out a very rare type of cervical cancer called minimal-deviation adenocarcinoma. The key distinguishing features are straightforward: a benign nabothian cyst appears round or oval on MRI without absorbing contrast dye, while a cancerous lesion behaves differently on imaging and often comes with a watery discharge. This distinction is only relevant for unusual presentations, not for the typical small cyst found during a routine exam.
When Treatment Is Needed
The short answer: almost never. Nabothian cysts are benign and don’t become cancerous. If a cyst is small and causing no symptoms, your provider will likely note it in your chart and leave it alone.
Treatment becomes a consideration in a few specific scenarios. A particularly large cyst, or a cluster of cysts, can physically block access to the cervix, making it difficult for your provider to collect cells during a Pap smear. In that case, the cyst may need to be drained or removed so routine screening can continue. Cysts that cause persistent discomfort during sex or create a noticeable sense of pressure may also be candidates for removal.
When removal is warranted, the procedures are straightforward and typically done in an office setting. Options include draining the cyst with a needle, using heat (electrocautery) to open and destroy it, or freezing it (cryotherapy). These are quick procedures with minimal recovery time. New cysts can form afterward through the same biological process that created the original, since the underlying tendency for squamous tissue to grow over glandular cells doesn’t change.
Effect on Fertility and Pregnancy
Nabothian cysts don’t affect your ability to get pregnant or carry a pregnancy. They sit on or within the surface of the cervix and don’t interfere with ovulation, the movement of sperm, or the function of the uterus. Because they’re so common and so rarely cause any functional problems, they aren’t considered a fertility concern. If you’re told you have one during a prenatal visit or fertility workup, it’s essentially an incidental finding with no bearing on your reproductive plans.