Bartholin's cyst develops when the entrance to the Bartholin duct becomes blocked. The gland continues to produce mucus which builds up behind the blockage, eventually leading to the formation of a mass. The initial blockage is most commonly caused by vulvar oedema. These are usually sterile.

Risk factors for the development of Bartholin's cyst are poorly understood, but it is thought to increase in incidence with increasing age up to the menopause before decreasing. In one published series, only 10% of cysts occurred in women over age 40. Having one cyst is a risk factor for developing a second.

Bartholin's cysts are usually unilateral and 1-3cm in diameter - the Bartholin's glands should not be palpable in health.

On examination, a cyst is characterised by the presence of a soft, painless lump in the labium. It is best felt between a finger at the posterior vaginal introitus and a thumb lateral to the labium.

Bartholin's cysts are usually painless and commonly asymptomatic, often being detected at a routine pelvic examination or by the woman herself. If the cyst is particularly large it may cause superficial dyspareunia and could be uncomfortable when sitting. In contrast, Bartholin's abscess is extremely painful, with erythema and often gross deformity of the affected side of the vulva. Bartholin's abscess is three times more common than the cyst in terms of presentations to gynaecology but this is likely to reflect the asymptomatic nature of the cyst in a majority of cases to some extent.

Asymptomatic cysts require no intervention in general, although in older women (over age 40) some gynaecologists advocate incision and drainage with biopsy in order to exclude carcinoma. Cysts that are symptomatic and/or disfiguring should be treated with either incision and drainage (with/without placement of a 'word' catheter to allow continuing drainage) or with a procedure known as marsupialisation. The latter involves the creation of a new orifice through which the glandular secretions may drain, by incising the gland open, everting it and suturing the epithelial lining against the skin. Marsupialisation is thought to be more effective at preventing recurrence, but is a longer operation and is more invasive. There is no place for antibiotic use in the setting of Bartholin's cyst with no evidence of abscess.