Introduction

Nabothian cysts, often referred to as Nabothian follicles, retention cysts, or cervical cysts, are benign growths that develop on the cervix, the lower portion of the uterus that joins to the vagina. The majority of these cysts are asymptomatic, implying that they typically don’t present any observable symptoms or health problems. Nabothian cysts are relatively common. They develop when the mucus-producing glands of the cervix become blocked, leading to the accumulation of mucus within a closed sac called a Nabothian cyst. During a standard pelvic exam, these cysts often appear as small, smooth, rounded lumps on the cervix. Nabothian cysts are typically harmless and may present as single growths or in multiple formations.¹

Most of the time, these cysts are unintentionally discovered during normal gynaecological exams or Pap screening examinations. Since they are non-cancerous and don’t pose any health risks, treatment is generally unnecessary. However, larger or symptomatic cysts may occasionally require drainage or removal by a medical expert. It is recommended to visit your gynaecologist (a doctor specialising in female reproductive health) regularly to monitor any changes in the size or appearance of Nabothian cysts.

Causes of nabothian cysts

When the uterine cervix undergoes chronic inflammation, either due to the healing process associated with chronic cervicitis or as part of the normal shedding of the uterus during the menstrual cycle, a proliferation of squamous epithelium (a type of skin cell) occurs. This proliferation results in the covering of the columnar epithelium of the endocervical glands, which are mucus-producing cells located near the inner cervix. The obstruction of the mucous-producing glands in the cervix results in the formation of cysts, known as Nabothian cysts. The cervix is home to a large number of endocervical glands, which produce mucus to help keep the cervix lubricated and shield it from infections. Small cysts are formed when the mucus builds up inside the glands due to the opening of these glands becoming blocked.² These cysts may enlarge over time and become noticeable on the cervix's surface during routine gynaecological exams. While these cysts are typically small, measuring just a few millimetres in diameter, they can occasionally grow to be 4 cm or larger.³

Risk factors

Nabothian cysts are benign lesions that develop on the cervix's surface. Despite being generally harmless and asymptomatic, several risk factors can contribute to their development. Hormonal imbalances, cervical infection, physical trauma, and a history of multiple pregnancies are among the risk factors associated with Nabothian cysts. In addition, women who have undergone cervical treatments such as biopsies or conization may have an increased risk of developing these cysts. However, it is important to remember that Nabothian cysts typically don’t cause concern and rarely require treatment unless they become large, cause discomfort, or obstruct normal cervical functions. 

Prevalence and demographic distribution

Nabothian cysts are quite common among women of reproductive age. The exact prevalence varies depending on demographic surveys, though they are generally considered a common finding during routine gynaecological exams. These cysts affect women of all racial and ethnic backgrounds equally. Although they are typically painless and harmless, they may be more prevalent in women who have experienced hormonal changes due to multiple pregnancies or cervical injuries. Routine pelvic exams are recommended for the early detection and management of these cysts.⁴

Signs and symptoms

Nabothian cysts are typically asymptomatic, meaning they don't produce any obvious symptoms. They are usually discovered incidentally during routine cervical screenings or pelvic exams. However, larger or multiple cysts may occasionally cause modest symptoms, such as:

• Vaginal discharge: The cysts may increase the production of cervical mucus, which could result in a white or clear vaginal discharge
• Pelvic pressure or discomfort: Large or multiple cysts may produce minor pelvic pressure or discomfort
• Pain during sex: In rare cases, large cysts may cause discomfort or pain during sex

Diagnosis

Nabothian cysts can be diagnosed using magnetic resonance imaging (MRI) and transvaginal ultrasonography. MRI can distinguish between normal (no cysts present) and pathological (cysts are present) situations, as well as differentiate between different types of growths or lesions within the cervix. It can distinguish between endophytic growths, which are caused by factors like bacterial or fungal infections penetrating into the tissue, and exophytic growths, which arise from the local tissue of the cervix itself. It is important to accurately diagnose Nabothian cysts to differentiate them from any malignant conditions, such as cancerous growths, which are very rare. Biopsy, conization, and endocervical curettage (a specialised type of biopsy) are effective investigative methods if cancer is suspected and MRI alone can’t rule it out. However, in the cases of unusually large and deep intracervical cysts, malignancy can’t always be ruled out through these biopsy methods. In such cases, an exploratory laparotomy (performed through the abdomen) may be necessary, or in extreme cases, a hysterectomy may be recommended.⁵

Differential diagnosis

The diagnosis of Nabothian cysts might be confused with other conditions, including:

• Adenoma malignum (a rare cancerous tumour that grows in the uterine cervix) 
• Glandular malignant cervical lesions
• Adenocarcinoma of the endocervical stoma, as it sometimes exhibits a cystic component that closely resembles benign Nabothian cysts⁴ 
• Leiomyomas
• Endometriosis
• Microglandular hyperplasia (localised noncancerous growth measuring 1-2 cm in the uterine cervix)
• Squamous papillomas (noncancerous, outward-growing lumps made up of squamous cells)
• Remains of the mesonephric duct (a primitive structure of the urinary system formed during a baby’s development in utero)⁴

Treatment and management

Nabothian cysts are benign and often asymptomatic, thus, treatment and management are primarily conservative. Medical intervention is typically unnecessary, as the cysts may spontaneously resolve. However, the following strategies may be considered if the cysts are large, uncomfortable, or interfering with cervical functions.

• Observation: In many cases, treatment may not be necessary, and monitoring the cysts through routine pelvic exams is sufficient to ensure they don't enlarge or cause complications
• Drainage: In certain situations, a healthcare professional may choose to aspirate or drain a sizable cyst to alleviate symptoms. However, recurrence is possible with this method.
• Surgery: If the cysts cause significant discomfort or if there are concerns about other cervical conditions, surgical options such as cryotherapy or electrocautery may be considered

Prognosis

Nabothian cysts generally have a good prognosis, as they rarely lead to serious health problems or complications and are benign. They often progress naturally in a stable or slow-growing manner, and may occasionally resolve without intervention. However, some cysts may persist or recur over time if removed.

FAQs

What are the complications of Nabothian cysts?

Nabothian cysts can lead to complications such as hematometra (retention of blood in the uterus), labour passage obstruction, rectal compression, abnormal uterine bleeding (especially in the case of giant cysts), and chronic urinary retention. This can occur due to obstruction of the bladder outlet or compression of the pudendal and sacral nerves, disrupting the nerve supply to the detrusor muscle (smooth muscle in the bladder wall).⁶ MRI can be used in these situations to locate Nabothian cysts.

How can I prevent Nabothian cysts?

Nabothian cysts are generally considered benign and common occurrences; however, they often arise from normal physiological processes and can’t be entirely prevented. Nevertheless, several measures may reduce the likelihood of developing Nabothian cysts, including:

• Practice safe sex: Lowering the risk of sexually transmitted infections can help reduce the possibility of cervical damage or inflammation, which may contribute to the development of Nabothian cysts
• Periodic gynaecological examinations: Regular cervical screenings and pelvic exams enable healthcare professionals to monitor any changes to the cervix, including the appearance of cysts
• Avoid cervical trauma: Limiting activities that could cause cervical trauma or damage, such as harsh sexual contact or improper use of devices, may be beneficial
• Maintain cervical health: Maintaining good overall hygiene and promptly seeking medical attention for infections or other gynaecological problems can help support a healthy cervix
• Hormonal balance: Maintaining hormonal balance, particularly during pregnancy and menopause, may be beneficial, as hormonal shifts can be associated with the development of some Nabothian cysts

Summary

Nabothian cysts are common, benign growths that develop on the surface of the cervix. They are asymptomatic, rarely cause complications, and are generally harmless. These cysts form due to the obstruction of the Nabothian glands, leading to excess production of mucus in the cervical tissue. Larger or multiple cysts may cause minor symptoms like vaginal discharge or pelvic discomfort. While Nabothian cysts are typically asymptomatic and may not require treatment, medical procedures such as drainage or surgical removal may be considered in cases of large or uncomfortable cysts. Nabothian cysts have a favourable prognosis, and these treatments are often low-risk. Early identification, monitoring, and maintaining good overall reproductive health rely on routine gynaecological exams.