Bartholin's abscess is the build-up of pus that forms a lump (swelling) in one of the Bartholin's glands, which are located on each side of the vaginal opening.
A Bartholin's abscess forms when a small opening (duct) from the gland gets blocked. Fluid in the gland builds up and may become infected. The infection is usually not caused by a sexually transmitted disease (STD). However, many types of bacteria associated with STDs, such as gonorrhea, can lead to infection.
Often the abscess appears and become very hot and swollen within 2 or 3 days. Any activity that puts pressure against the vulva, even walking and sitting, may cause excruciating pain.